n Abstract: Chronic pain has been shown to affect up to 60% of patients undergoing surgery for br... more n Abstract: Chronic pain has been shown to affect up to 60% of patients undergoing surgery for breast cancer. Besides younger age, other risk factors for the development of chronic pain have not been consistent in previous studies. The objective of the current investigation was to detect the prevalence and risk factors for the development of chronic pain after breast cancer surgery by examining a patient population from a tertiary cancer center in the United States. The study was a prospective observational cohort study. Subjects were evaluated at least 6 months after the surgical procedure. Subjects responded to the modified short form Brief pain inventory and the short form McGill pain questionnaire to identify and characterize pain. Demographic, surgery, cancer treatment, and perioperative characteristics were recorded. Propensity matching regression analysis were used to examine risk factors associated with the development of chronic pain. 300 patients were included in the study. 110 reported the presence of chronic pain. Subjects with chronic pain reported median (interquartile range [IQR]) rating of worst pain in the last 24 hours of 4 (2-5) and a median (IQR) rating on average pain in the last 24 hours of 3 (1-4) on a 0-10 numeric rating scale. Independent risk factors associated with the development of chronic pain were age, OR (95% CI) of 0.95 (0.93-0.98) and axillary lymph node dissection, 7.7 (4.3-13.9) but not radiation therapy, 1.05(0.56-1.95). After propensity matching for confounding covariates, radiation was still not associated with the development of chronic pain. Chronic pain after mastectomy continues to have a high prevalence in breast cancer patients. Younger age and axillary lymph node dissection but not radiation therapy are risk factors for the development of chronic pain. Preventive strategies to minimize the development of chronic pain are highly desirable. n
Objectives: To compare if mastectomy with reconstructive surgery had greater incidence of chronic... more Objectives: To compare if mastectomy with reconstructive surgery had greater incidence of chronic pain compared to mastectomy surgery alone. Materials and methods: The study was a retrospective cohort. Patients who underwent mastectomies with and without reconstruction responded to the modified short form Brief Pain Inventory and the short form McGill pain questionnaire to identify and characterize pain at least 6 months after the surgical procedure. Propensity matching analysis was used to control for covariates differences in the study groups. Results: 310 subjects were included and 132 patients (43%) reported the presence of chronic pain. After propensity score matching to adjust for covariate imbalances, the incidence of chronic pain in the mastectomy group who had additional surgery for breast reconstruction was not different compared to the group who had mastectomy surgery alone, 26 out of 68 (38%) and 27 out of 68 (39%), respectively P ¼ 1.0. Among patients who had chronic pain, breast reconstruction did not increase the intensity of worst pain in the last 24 h, median (IQR) of 2 (1e5) compared to 4 (1e5) in the no reconstruction group, P ¼ 0.41. Type of reconstruction (breast implants vs. flap tissue) did not result in greater incidence and/or intensity of chronic pain. Conclusions: Breast reconstruction after mastectomy does not result in a greater incidence of chronic pain compared to mastectomy alone. Female patients undergoing breast cancer surgery should not incorporate chronic pain in their decision to undergo reconstructive surgery after mastectomy.
Previous evidence suggested that 10 mg systemic metoclopramide is not effective to prevent postop... more Previous evidence suggested that 10 mg systemic metoclopramide is not effective to prevent postoperative nausea and/or vomiting (PONV) in patients receiving general anaesthesia. However, the evidence included data with questioned validity by the author Yoshitaka Fujii. The objective of the current study was to examine the effect of a systemic dose of 10 mg metoclopramide to prevent PONV. This quantitative systematic review was performed according to the PRISMA guidelines. A wide search was performed to identify randomized clinical trials that evaluated systemic 10 mg metoclopramide as a prophylactic agent to reduce PONV. Meta-analysis was performed using a random-effect model. Thirty trials evaluating the effect of 10 mg systemic metoclopramide in 3328 subjects on PONV outcomes were included. Metoclopramide reduced the incidence of 24 h PONV compared with control, odds ratio (OR) [95% confidence interval (CI)] of 0.58 (0.43-0.78), number needed to treat (NNT)=7.8. When evaluated as separate outcomes, metoclopramide also decreased the incidence of nausea over 24 h, OR (95% CI) of 0.51 (0.38-0.68), NNT=7.1, and vomiting over 24 h, OR (95% CI) of 0.51 (0.40-0.66), NNT=8.3. A post hoc analysis examining three studies with questioned validity performed by the author Yoshitaka Fujii that would meet criteria for inclusion in the current study did not demonstrate a significant benefit of metoclopramide compared with control on the incidence of 24 h PONV. Our findings suggest that metoclopramide 10 mg i.v. is effective to prevent PONV in patients having surgical procedures under general anaesthesia. Metoclopramide seems to be a reasonable agent to prevent PONV.
The prevalence of burnout and depression in anesthesiology residents has not been determined. It ... more The prevalence of burnout and depression in anesthesiology residents has not been determined. It is also unknown whether anesthesiology resident burnout/depression may affect patient care and safety. The primary objective of this study was to determine the prevalence of burnout and depression in anesthesiology residents in the United States. We hypothesized that residents at high risk of burnout and/or depression would report more medical errors as well as a lower rate of following principles identified as the best practice of anesthesiology. A cross-sectional survey was sent to 2773 anesthesiology residents in the United States. The questionnaire was divided into 5 parts examining trainees' demographic factors, burnout (Maslach Burnout Inventory), depression (Harvard depression scale), 10 questions designed to evaluate best practice of anesthesiology, and 7 questions evaluating self-reported errors. Best practices and self-reported error rates were compared among subjects with a high risk of burnout only, high risk of depression only, high risk of burnout and depression, and low risk of burnout and depression. Pairwise comparisons were considered significant at P < 0.004 and confidence intervals (CIs) reported at 99.6%. There were 1508 (54%) resident responds. High burnout risk was found in 41% (575 of 1417) of respondents. Working >70 hours per week, having >5 drinks per week, and female gender were associated with increased burnout risk. Twenty-two percent (298 of 1384) screened positive for depression. Working >70 hours of work per week, smoking, female gender, and having >5 drinks per week were associated with increased depression risk. Two hundred forty (17%) respondents scored at high risk of burnout and depression, 321 (23%) at high risk of burnout, 58 (4%) at high risk of depression only, and 764 (56%) at low risk of burnout or depression. Median best practice scores (maximum = 30) for residents at high risk of burnout (difference -2; 99.6% CI, -1 to -2; P < 0.001) or high risk of burnout and depression (difference -4; 99.6% CI, -3 to -6; P…
Poor supervision of physician trainees can be detrimental not only to resident education but also... more Poor supervision of physician trainees can be detrimental not only to resident education but also to patient care and safety. Inadequate supervision has been associated with more frequent deaths of patients under the care of junior residents. We hypothesized that residents reporting more medical errors would also report lower quality of supervision scores than the ones with lower reported medical errors. The primary objective of this study was to evaluate the association between the frequency of medical errors reported by residents and their perceived quality of faculty supervision. A cross-sectional nationwide survey was sent to 1000 residents randomly selected from anesthesiology training departments across the United States. Residents from 122 residency programs were invited to participate, the median (interquartile range) per institution was 7 (4-11). Participants were asked to complete a survey assessing demography, perceived quality of faculty supervision, and perceived causes of inadequate perceived supervision. Responses to the statements "I perform procedures for which I am not properly trained," "I make mistakes that have negative consequences for the patient," and "I have made a medication error (drug or incorrect dose) in the last year" were used to assess error rates. Average supervision scores were determined using the De Oliveira Filho et al. scale and compared among the frequency of self-reported error categories using the Kruskal-Wallis test. Six hundred four residents responded to the survey (60.4%). Forty-five (7.5%) of the respondents reported performing procedures for which they were not properly trained, 24 (4%) reported having made mistakes with negative consequences to patients, and 16 (3%) reported medication errors in the last year having occurred multiple times or often. Supervision scores were inversely correlated with the frequency of reported errors for all 3 questions evaluating errors. At a cutoff value of 3, supervision scores demonstrated an overall accuracy (area under the curve) (99% confidence interval) of 0.81 (0.73-0.86), 0.89 (0.77-0.95), and 0.93 (0.77-0.98) for predicting a response of multiple times or often to the question of performing procedures for which they were not properly trained, reported mistakes with negative consequences to patients, and reported medication errors in the last year, respectively. Anesthesiology trainees who reported a greater incidence of medical errors with negative consequences to patients and drug errors also reported lower scores for supervision by faculty. Our findings suggest that further studies of the association between supervision and patient safety are warranted. (Anesth Analg 2013;116:892-7).
Publication bias occurs because positive finding studies are more likely to be published. The dea... more Publication bias occurs because positive finding studies are more likely to be published. The dearth of studies of negative or equivalence findings can erroneously affect future research and potentially clinical care of patients. We hypothesized that positive studies were more likely to be published than negative studies in anesthesiology journals with a higher impact and circulation. A PubMed search for controlled trials in humans published in peer-reviewed anesthesiology journals during 2008 and 2009 was performed. Fourteen anesthesiology journals and 1163 studies were evaluated. The average clinical trial impact factor (average citations per article) for each journal was determined. The quartiles for the clinical trial impact factor for the journals included in the analysis were 4, 6.1, and 9.1. Studies were scored by 2 raters as positive or negative results of the primary stated outcome. Factors previously associated with publication were also extracted. The primary outcome, the proportion of positive and negative studies in the journals in the upper quartile of the clinical trial impact factor to the lower quartiles was compared using the Fisher exact test. The odds ratio for the effect of positive study results adjusted for other characteristics associated with publication was determined using binary logistic regression. A multinomial logistic regression model was fitted for the journals with an impact factor in the upper quartile with adjustment for study trial registration, origin of publication, positive study findings, reporting of treatment blinding, reporting of subject withdrawals, study sponsorship, and description of the randomization method. Positive finding studies were identified in 72% (425 of 588) of articles in journals with a clinical trial impact factor >9.1 compared with 53% (308 of 575) in journals <9.1 (P < 0.001). After adjusting for factors associated with publication, positive study results had an odds ratio (95% confidence interval) of 2.28 (1.76-3.01) for publication in an anesthesiology journal in the upper quartile. Multinomial logistic regression identified positive study findings associated with an increased likelihood of publication in 3 of the 4 anesthesiology journals with a clinical trial impact factor >9.1. This study reports the presence of publication bias in the anesthesiology literature especially in higher clinical trial impact factor journals. Publication bias can have potential implications for future research and the clinical care of patients. Authors should be encouraged to submit negative studies to high impact journals and the journals should be encouraged to evaluate the editorial process as the cause of publication bias.
We developed a virtual reality software application (iLarynx) using built-in accelerometer proper... more We developed a virtual reality software application (iLarynx) using built-in accelerometer properties of the iPhone(®) or iPad(®) (Apple Inc., Cupertino, CA, USA) that mimics hand movements for the performance of fibreoptic skills. Twenty novice medical students were randomly assigned to virtual airway training with the iLarynx software or no additional training. Eight out of the 10 subjects in the standard training group had at least one failed (> 120 s) attempt compared with two out of the 10 participants in the iLarynx group (p = 0.01). There were a total of 24 failed attempts in the standard training group and four in the iLarynx group (p < 0.005). Cusum analysis demonstrated continued group improvement in the iLarynx, but not in the standard training group. Virtual airway simulation using freely available software on a smartphone/tablet device improves dexterity among novices performing upper airway endoscopy.
The era of big data has created new opportunities for researchers to achieve high relevance and i... more The era of big data has created new opportunities for researchers to achieve high relevance and impact amid changes and transformations in how we study social science phenomena. With the emergence of new data collection technologies, advanced data mining and analytics support, there seems to be fundamental changes that are occurring with the research questions we can ask, and the research methods we can apply. The contexts include social networks and blogs, political discourse, corporate announcements, digital journalism, mobile telephony, home entertainment, online gaming, financial services, online shopping, social advertising, and social commerce. The changing costs of data collection and the new capabilities that researchers have to conduct research that leverages micro-level, meso-level and macro-level data suggest the possibility of a scientific paradigm shift toward computational social science. The new thinking related to empirical regularities analysis, experimental design, and longitudinal empirical research further suggests that these approaches can be tailored for rapid acquisition of big data sets. This will allow business analysts and researchers to achieve frequent, controlled and meaningful observations of realworld phenomena. We discuss how our philosophy of science should be changing in step with the times, and illustrate our perspective with comparisons between earlier and current research inquiry. We argue against the assertion that theory no longer matters and offer some new research directions. "To get value from big data, 'quants' or data scientists are becoming analytic innovators who create tremendous business value within an organization, quickly exploring and uncovering game-changing insights from vast volumes of data, as opposed to merely accessing transactional data for operational reporting." Randy Lee, Vice President, Aster Center for Data Innovation, Teradata "The best way to engage in … data-driven marketing is to gather more and more specific information about customer preferences, run experiments and analyses on the new data, and determine ways of appealing to [casino game] players' interests. We realized that the information in our database, couple with decision science tools that enabled us to predict individual customer's theoretical value to us, would allow us to create marketing interventions that profitably addressed players' unique preferences."
We analyze TV subscribers channel usage patterns in terms of three factors affecting the diversit... more We analyze TV subscribers channel usage patterns in terms of three factors affecting the diversity of viewing in the households: channel subscriptions, genre preferences and viewing time. We use data collected from advanced cable TV set-top boxes deployed in hundreds of thousands of households in Singapore. We perform cluster analysis to identify viewership patterns, and estimate two explanatory models, based on different distributional assumptions for household TV channels in terms of the efficiency of channel usage and concentration of viewing time on specific channels. Our extended analysis probes issues related to the stratification of the data, and the range of values for some of the independent variables. For this, we apply quantile and spline regression methods. We obtained these insights: viewing efficiency decreases as viewers have more subscribed channels available; viewers with more available time watch more channels but tend to concentrate watching their favorite channels; and the genre of programming that is most watched affects the diversity of household viewing. We draw a number of conclusions that are intended to offer cable TV services providers with ideas to support development of new strategies.
Consumer behavior related to digital media in the home is subject to changing patterns due to the... more Consumer behavior related to digital media in the home is subject to changing patterns due to the rise of technological innovations that support new behavioral patterns. This research examines patterns of consumer behavior in the presence of two-way cable television (CATV) set-top boxes. These are technical devices that permit media viewers to change channels, switch to the Internet, and order paid programming, among other emerging functions. Our research focuses on the most advanced of these devices, and the micro-level data that are generated from consumer behavior in this context. This permits us to capture clickstreams of channelchanging behavior that consumers create when they use a remote control handset to interact with the set-top box in their home. We explore a variety of data analytics results that characterize patterns of consumer channel-switching behavior, as a basis for suggesting different clusters of observed behavior, and further probing the explanatory elements that give rise to what we see.
Emerging technologies have created disruptions in organizational, business process and industry c... more Emerging technologies have created disruptions in organizational, business process and industry contexts. They act as shocks to a system. We focus on a retail telecom service provider's offerings of different bundles, including mobile phones, Internet and cable TV services. We conduct empirical regularities analysis for Singapore, which was affected by the emergence of smartphones in 2009. We assess the impacts on the service bundle choices of a provider's customers. We analyze customer switching among service bundles involving three services. We compute switching probabilities for each of the service levels offered, as well as between bundles. We use Markov chain transition analysis to describe the patterns. We find evidence for: smartphone effects on the contents of service demand; substitution between different kinds of Internet services; and migration of video consumption from cable TV to mobile services. Our results provide a basis for improved management of retail services bundling and pricing strategies.
Given that OIAs differ substantially from traditional, closed alliances in many aspects, includin... more Given that OIAs differ substantially from traditional, closed alliances in many aspects, including their strategic scope and scale, governing mechanisms, and member composition, it is important to understand and assess the potential value inherent in these new modes of collaboration. Furthermore, OIAs evolve over time as the participating members are free to enter and leave at will. Therefore, we also examine the on-going value creation and wealth spillover that result from changes in membership. Moreover, we investigate how a firm's participation in an IT-based open alliance alters the market value of its rivals operating within the same marketplace. To gain additional insight into the factors that moderate the market valuation of OIA participation, several contextual factors, including the degree of partner heterogeneity, innovation type, and degree of openness of the OIAs are used to account for variability in abnormal returns. Based on 194 observations, we found that allying firms realize significant positive abnormal returns when their entry into an OIA is made public. The results also suggest that substantial excessive returns accrue to the allying firms with the belated entry of a market leader firm. Furthermore, we discovered that a firm's entry into an OIA increases, rather than decreases, the market valuation of its rival. Interestingly, an incumbent rival that did not participate in the alliance appears to gain greater "free-riding" benefits from the OIA, as compared to peer rivals. Innovation type and openness were significantly associated with the amount of abnormal returns accruing to allying firms, while no significance was found for partner heterogeneity. Finally, we conclude with a discussion of the implications of our findings for research and practice with respect to value cocreation in multifirm environments.
U sing agent-based simulation experiments, we investigate the outcome of SAs between two smaller ... more U sing agent-based simulation experiments, we investigate the outcome of SAs between two smaller online search engine companies in competition with a dominant market leader in settings where an advertiser's decision making is the consequence of a combination of NI (e.g., an individual's willingness to follow others' decisions) and IP. In particular, we focus on a context in which the combined search engine company competes with a market leader holding a larger share of the market than the two runner-up "underdogs" combined.
This paper discusses a lot grouping problem for a continuous slab caster in an integrated steel m... more This paper discusses a lot grouping problem for a continuous slab caster in an integrated steel mill. Molten steel called'charge'is transported to the continuous caster to be cast as the elongated rectangular solid steel pieces called'slabs' of various sizes and metallurgical compositions. In order to enhance the productivity of the continuous caster, it is preferable to group as many charges as possible to form the cast.
n Abstract: Chronic pain has been shown to affect up to 60% of patients undergoing surgery for br... more n Abstract: Chronic pain has been shown to affect up to 60% of patients undergoing surgery for breast cancer. Besides younger age, other risk factors for the development of chronic pain have not been consistent in previous studies. The objective of the current investigation was to detect the prevalence and risk factors for the development of chronic pain after breast cancer surgery by examining a patient population from a tertiary cancer center in the United States. The study was a prospective observational cohort study. Subjects were evaluated at least 6 months after the surgical procedure. Subjects responded to the modified short form Brief pain inventory and the short form McGill pain questionnaire to identify and characterize pain. Demographic, surgery, cancer treatment, and perioperative characteristics were recorded. Propensity matching regression analysis were used to examine risk factors associated with the development of chronic pain. 300 patients were included in the study. 110 reported the presence of chronic pain. Subjects with chronic pain reported median (interquartile range [IQR]) rating of worst pain in the last 24 hours of 4 (2-5) and a median (IQR) rating on average pain in the last 24 hours of 3 (1-4) on a 0-10 numeric rating scale. Independent risk factors associated with the development of chronic pain were age, OR (95% CI) of 0.95 (0.93-0.98) and axillary lymph node dissection, 7.7 (4.3-13.9) but not radiation therapy, 1.05(0.56-1.95). After propensity matching for confounding covariates, radiation was still not associated with the development of chronic pain. Chronic pain after mastectomy continues to have a high prevalence in breast cancer patients. Younger age and axillary lymph node dissection but not radiation therapy are risk factors for the development of chronic pain. Preventive strategies to minimize the development of chronic pain are highly desirable. n
Objectives: To compare if mastectomy with reconstructive surgery had greater incidence of chronic... more Objectives: To compare if mastectomy with reconstructive surgery had greater incidence of chronic pain compared to mastectomy surgery alone. Materials and methods: The study was a retrospective cohort. Patients who underwent mastectomies with and without reconstruction responded to the modified short form Brief Pain Inventory and the short form McGill pain questionnaire to identify and characterize pain at least 6 months after the surgical procedure. Propensity matching analysis was used to control for covariates differences in the study groups. Results: 310 subjects were included and 132 patients (43%) reported the presence of chronic pain. After propensity score matching to adjust for covariate imbalances, the incidence of chronic pain in the mastectomy group who had additional surgery for breast reconstruction was not different compared to the group who had mastectomy surgery alone, 26 out of 68 (38%) and 27 out of 68 (39%), respectively P ¼ 1.0. Among patients who had chronic pain, breast reconstruction did not increase the intensity of worst pain in the last 24 h, median (IQR) of 2 (1e5) compared to 4 (1e5) in the no reconstruction group, P ¼ 0.41. Type of reconstruction (breast implants vs. flap tissue) did not result in greater incidence and/or intensity of chronic pain. Conclusions: Breast reconstruction after mastectomy does not result in a greater incidence of chronic pain compared to mastectomy alone. Female patients undergoing breast cancer surgery should not incorporate chronic pain in their decision to undergo reconstructive surgery after mastectomy.
Previous evidence suggested that 10 mg systemic metoclopramide is not effective to prevent postop... more Previous evidence suggested that 10 mg systemic metoclopramide is not effective to prevent postoperative nausea and/or vomiting (PONV) in patients receiving general anaesthesia. However, the evidence included data with questioned validity by the author Yoshitaka Fujii. The objective of the current study was to examine the effect of a systemic dose of 10 mg metoclopramide to prevent PONV. This quantitative systematic review was performed according to the PRISMA guidelines. A wide search was performed to identify randomized clinical trials that evaluated systemic 10 mg metoclopramide as a prophylactic agent to reduce PONV. Meta-analysis was performed using a random-effect model. Thirty trials evaluating the effect of 10 mg systemic metoclopramide in 3328 subjects on PONV outcomes were included. Metoclopramide reduced the incidence of 24 h PONV compared with control, odds ratio (OR) [95% confidence interval (CI)] of 0.58 (0.43-0.78), number needed to treat (NNT)=7.8. When evaluated as separate outcomes, metoclopramide also decreased the incidence of nausea over 24 h, OR (95% CI) of 0.51 (0.38-0.68), NNT=7.1, and vomiting over 24 h, OR (95% CI) of 0.51 (0.40-0.66), NNT=8.3. A post hoc analysis examining three studies with questioned validity performed by the author Yoshitaka Fujii that would meet criteria for inclusion in the current study did not demonstrate a significant benefit of metoclopramide compared with control on the incidence of 24 h PONV. Our findings suggest that metoclopramide 10 mg i.v. is effective to prevent PONV in patients having surgical procedures under general anaesthesia. Metoclopramide seems to be a reasonable agent to prevent PONV.
The prevalence of burnout and depression in anesthesiology residents has not been determined. It ... more The prevalence of burnout and depression in anesthesiology residents has not been determined. It is also unknown whether anesthesiology resident burnout/depression may affect patient care and safety. The primary objective of this study was to determine the prevalence of burnout and depression in anesthesiology residents in the United States. We hypothesized that residents at high risk of burnout and/or depression would report more medical errors as well as a lower rate of following principles identified as the best practice of anesthesiology. A cross-sectional survey was sent to 2773 anesthesiology residents in the United States. The questionnaire was divided into 5 parts examining trainees' demographic factors, burnout (Maslach Burnout Inventory), depression (Harvard depression scale), 10 questions designed to evaluate best practice of anesthesiology, and 7 questions evaluating self-reported errors. Best practices and self-reported error rates were compared among subjects with a high risk of burnout only, high risk of depression only, high risk of burnout and depression, and low risk of burnout and depression. Pairwise comparisons were considered significant at P < 0.004 and confidence intervals (CIs) reported at 99.6%. There were 1508 (54%) resident responds. High burnout risk was found in 41% (575 of 1417) of respondents. Working >70 hours per week, having >5 drinks per week, and female gender were associated with increased burnout risk. Twenty-two percent (298 of 1384) screened positive for depression. Working >70 hours of work per week, smoking, female gender, and having >5 drinks per week were associated with increased depression risk. Two hundred forty (17%) respondents scored at high risk of burnout and depression, 321 (23%) at high risk of burnout, 58 (4%) at high risk of depression only, and 764 (56%) at low risk of burnout or depression. Median best practice scores (maximum = 30) for residents at high risk of burnout (difference -2; 99.6% CI, -1 to -2; P < 0.001) or high risk of burnout and depression (difference -4; 99.6% CI, -3 to -6; P…
Poor supervision of physician trainees can be detrimental not only to resident education but also... more Poor supervision of physician trainees can be detrimental not only to resident education but also to patient care and safety. Inadequate supervision has been associated with more frequent deaths of patients under the care of junior residents. We hypothesized that residents reporting more medical errors would also report lower quality of supervision scores than the ones with lower reported medical errors. The primary objective of this study was to evaluate the association between the frequency of medical errors reported by residents and their perceived quality of faculty supervision. A cross-sectional nationwide survey was sent to 1000 residents randomly selected from anesthesiology training departments across the United States. Residents from 122 residency programs were invited to participate, the median (interquartile range) per institution was 7 (4-11). Participants were asked to complete a survey assessing demography, perceived quality of faculty supervision, and perceived causes of inadequate perceived supervision. Responses to the statements "I perform procedures for which I am not properly trained," "I make mistakes that have negative consequences for the patient," and "I have made a medication error (drug or incorrect dose) in the last year" were used to assess error rates. Average supervision scores were determined using the De Oliveira Filho et al. scale and compared among the frequency of self-reported error categories using the Kruskal-Wallis test. Six hundred four residents responded to the survey (60.4%). Forty-five (7.5%) of the respondents reported performing procedures for which they were not properly trained, 24 (4%) reported having made mistakes with negative consequences to patients, and 16 (3%) reported medication errors in the last year having occurred multiple times or often. Supervision scores were inversely correlated with the frequency of reported errors for all 3 questions evaluating errors. At a cutoff value of 3, supervision scores demonstrated an overall accuracy (area under the curve) (99% confidence interval) of 0.81 (0.73-0.86), 0.89 (0.77-0.95), and 0.93 (0.77-0.98) for predicting a response of multiple times or often to the question of performing procedures for which they were not properly trained, reported mistakes with negative consequences to patients, and reported medication errors in the last year, respectively. Anesthesiology trainees who reported a greater incidence of medical errors with negative consequences to patients and drug errors also reported lower scores for supervision by faculty. Our findings suggest that further studies of the association between supervision and patient safety are warranted. (Anesth Analg 2013;116:892-7).
Publication bias occurs because positive finding studies are more likely to be published. The dea... more Publication bias occurs because positive finding studies are more likely to be published. The dearth of studies of negative or equivalence findings can erroneously affect future research and potentially clinical care of patients. We hypothesized that positive studies were more likely to be published than negative studies in anesthesiology journals with a higher impact and circulation. A PubMed search for controlled trials in humans published in peer-reviewed anesthesiology journals during 2008 and 2009 was performed. Fourteen anesthesiology journals and 1163 studies were evaluated. The average clinical trial impact factor (average citations per article) for each journal was determined. The quartiles for the clinical trial impact factor for the journals included in the analysis were 4, 6.1, and 9.1. Studies were scored by 2 raters as positive or negative results of the primary stated outcome. Factors previously associated with publication were also extracted. The primary outcome, the proportion of positive and negative studies in the journals in the upper quartile of the clinical trial impact factor to the lower quartiles was compared using the Fisher exact test. The odds ratio for the effect of positive study results adjusted for other characteristics associated with publication was determined using binary logistic regression. A multinomial logistic regression model was fitted for the journals with an impact factor in the upper quartile with adjustment for study trial registration, origin of publication, positive study findings, reporting of treatment blinding, reporting of subject withdrawals, study sponsorship, and description of the randomization method. Positive finding studies were identified in 72% (425 of 588) of articles in journals with a clinical trial impact factor >9.1 compared with 53% (308 of 575) in journals <9.1 (P < 0.001). After adjusting for factors associated with publication, positive study results had an odds ratio (95% confidence interval) of 2.28 (1.76-3.01) for publication in an anesthesiology journal in the upper quartile. Multinomial logistic regression identified positive study findings associated with an increased likelihood of publication in 3 of the 4 anesthesiology journals with a clinical trial impact factor >9.1. This study reports the presence of publication bias in the anesthesiology literature especially in higher clinical trial impact factor journals. Publication bias can have potential implications for future research and the clinical care of patients. Authors should be encouraged to submit negative studies to high impact journals and the journals should be encouraged to evaluate the editorial process as the cause of publication bias.
We developed a virtual reality software application (iLarynx) using built-in accelerometer proper... more We developed a virtual reality software application (iLarynx) using built-in accelerometer properties of the iPhone(®) or iPad(®) (Apple Inc., Cupertino, CA, USA) that mimics hand movements for the performance of fibreoptic skills. Twenty novice medical students were randomly assigned to virtual airway training with the iLarynx software or no additional training. Eight out of the 10 subjects in the standard training group had at least one failed (> 120 s) attempt compared with two out of the 10 participants in the iLarynx group (p = 0.01). There were a total of 24 failed attempts in the standard training group and four in the iLarynx group (p < 0.005). Cusum analysis demonstrated continued group improvement in the iLarynx, but not in the standard training group. Virtual airway simulation using freely available software on a smartphone/tablet device improves dexterity among novices performing upper airway endoscopy.
The era of big data has created new opportunities for researchers to achieve high relevance and i... more The era of big data has created new opportunities for researchers to achieve high relevance and impact amid changes and transformations in how we study social science phenomena. With the emergence of new data collection technologies, advanced data mining and analytics support, there seems to be fundamental changes that are occurring with the research questions we can ask, and the research methods we can apply. The contexts include social networks and blogs, political discourse, corporate announcements, digital journalism, mobile telephony, home entertainment, online gaming, financial services, online shopping, social advertising, and social commerce. The changing costs of data collection and the new capabilities that researchers have to conduct research that leverages micro-level, meso-level and macro-level data suggest the possibility of a scientific paradigm shift toward computational social science. The new thinking related to empirical regularities analysis, experimental design, and longitudinal empirical research further suggests that these approaches can be tailored for rapid acquisition of big data sets. This will allow business analysts and researchers to achieve frequent, controlled and meaningful observations of realworld phenomena. We discuss how our philosophy of science should be changing in step with the times, and illustrate our perspective with comparisons between earlier and current research inquiry. We argue against the assertion that theory no longer matters and offer some new research directions. "To get value from big data, 'quants' or data scientists are becoming analytic innovators who create tremendous business value within an organization, quickly exploring and uncovering game-changing insights from vast volumes of data, as opposed to merely accessing transactional data for operational reporting." Randy Lee, Vice President, Aster Center for Data Innovation, Teradata "The best way to engage in … data-driven marketing is to gather more and more specific information about customer preferences, run experiments and analyses on the new data, and determine ways of appealing to [casino game] players' interests. We realized that the information in our database, couple with decision science tools that enabled us to predict individual customer's theoretical value to us, would allow us to create marketing interventions that profitably addressed players' unique preferences."
We analyze TV subscribers channel usage patterns in terms of three factors affecting the diversit... more We analyze TV subscribers channel usage patterns in terms of three factors affecting the diversity of viewing in the households: channel subscriptions, genre preferences and viewing time. We use data collected from advanced cable TV set-top boxes deployed in hundreds of thousands of households in Singapore. We perform cluster analysis to identify viewership patterns, and estimate two explanatory models, based on different distributional assumptions for household TV channels in terms of the efficiency of channel usage and concentration of viewing time on specific channels. Our extended analysis probes issues related to the stratification of the data, and the range of values for some of the independent variables. For this, we apply quantile and spline regression methods. We obtained these insights: viewing efficiency decreases as viewers have more subscribed channels available; viewers with more available time watch more channels but tend to concentrate watching their favorite channels; and the genre of programming that is most watched affects the diversity of household viewing. We draw a number of conclusions that are intended to offer cable TV services providers with ideas to support development of new strategies.
Consumer behavior related to digital media in the home is subject to changing patterns due to the... more Consumer behavior related to digital media in the home is subject to changing patterns due to the rise of technological innovations that support new behavioral patterns. This research examines patterns of consumer behavior in the presence of two-way cable television (CATV) set-top boxes. These are technical devices that permit media viewers to change channels, switch to the Internet, and order paid programming, among other emerging functions. Our research focuses on the most advanced of these devices, and the micro-level data that are generated from consumer behavior in this context. This permits us to capture clickstreams of channelchanging behavior that consumers create when they use a remote control handset to interact with the set-top box in their home. We explore a variety of data analytics results that characterize patterns of consumer channel-switching behavior, as a basis for suggesting different clusters of observed behavior, and further probing the explanatory elements that give rise to what we see.
Emerging technologies have created disruptions in organizational, business process and industry c... more Emerging technologies have created disruptions in organizational, business process and industry contexts. They act as shocks to a system. We focus on a retail telecom service provider's offerings of different bundles, including mobile phones, Internet and cable TV services. We conduct empirical regularities analysis for Singapore, which was affected by the emergence of smartphones in 2009. We assess the impacts on the service bundle choices of a provider's customers. We analyze customer switching among service bundles involving three services. We compute switching probabilities for each of the service levels offered, as well as between bundles. We use Markov chain transition analysis to describe the patterns. We find evidence for: smartphone effects on the contents of service demand; substitution between different kinds of Internet services; and migration of video consumption from cable TV to mobile services. Our results provide a basis for improved management of retail services bundling and pricing strategies.
Given that OIAs differ substantially from traditional, closed alliances in many aspects, includin... more Given that OIAs differ substantially from traditional, closed alliances in many aspects, including their strategic scope and scale, governing mechanisms, and member composition, it is important to understand and assess the potential value inherent in these new modes of collaboration. Furthermore, OIAs evolve over time as the participating members are free to enter and leave at will. Therefore, we also examine the on-going value creation and wealth spillover that result from changes in membership. Moreover, we investigate how a firm's participation in an IT-based open alliance alters the market value of its rivals operating within the same marketplace. To gain additional insight into the factors that moderate the market valuation of OIA participation, several contextual factors, including the degree of partner heterogeneity, innovation type, and degree of openness of the OIAs are used to account for variability in abnormal returns. Based on 194 observations, we found that allying firms realize significant positive abnormal returns when their entry into an OIA is made public. The results also suggest that substantial excessive returns accrue to the allying firms with the belated entry of a market leader firm. Furthermore, we discovered that a firm's entry into an OIA increases, rather than decreases, the market valuation of its rival. Interestingly, an incumbent rival that did not participate in the alliance appears to gain greater "free-riding" benefits from the OIA, as compared to peer rivals. Innovation type and openness were significantly associated with the amount of abnormal returns accruing to allying firms, while no significance was found for partner heterogeneity. Finally, we conclude with a discussion of the implications of our findings for research and practice with respect to value cocreation in multifirm environments.
U sing agent-based simulation experiments, we investigate the outcome of SAs between two smaller ... more U sing agent-based simulation experiments, we investigate the outcome of SAs between two smaller online search engine companies in competition with a dominant market leader in settings where an advertiser's decision making is the consequence of a combination of NI (e.g., an individual's willingness to follow others' decisions) and IP. In particular, we focus on a context in which the combined search engine company competes with a market leader holding a larger share of the market than the two runner-up "underdogs" combined.
This paper discusses a lot grouping problem for a continuous slab caster in an integrated steel m... more This paper discusses a lot grouping problem for a continuous slab caster in an integrated steel mill. Molten steel called'charge'is transported to the continuous caster to be cast as the elongated rectangular solid steel pieces called'slabs' of various sizes and metallurgical compositions. In order to enhance the productivity of the continuous caster, it is preferable to group as many charges as possible to form the cast.
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Papers by Ray Chang