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Kevin McLaughlin

Publications and source records attributed to Kevin McLaughlin.

At least 19 recordsLinked to original sources
PubMed2006

Can concept sorting provide a reliable, valid and sensitive measure of medical knowledge structure?

CONTEXT: Evolution from novice to expert is associated with the development of expert-type knowledge structure. The objectives of this study were to examine reliability and validity of concept sorting (ConSort) as a measure of static knowledge structure and to determine the relationship between concepts in static knowledge structure and concepts used during diagnostic reasoning. METHOD: ConSort was used to identify static knowledge concepts and analysis of think-aloud protocols was used to identify dynamic knowledge concepts (used during diagnostic reasoning). Intra- and inter-rater reliability, and correlation across cases, were evaluated. Construct validity was evaluated by comparing proportions of nephrologists and students with expert-type knowledge structure. Sensitivity and specificity of static knowledge concepts as a predictor of dynamic knowledge concepts were estimated. RESULTS: Thirteen first-year medical students and 19 nephrologists participated. Intra- and inter-rater agreement for determination of static knowledge concepts were 1.0 and 0.90, respectively. Reliability across cases was 0.45. The proportions of nephrologists and students identified as having expert-type knowledge structure were 82.9% and 55.8%, respectively (p=0.001). Sensitivity and specificity of ConSort((c)) in predicting concepts that were used during diagnostic reasoning were 96.8% and 27.8% for nephrologists and 87.2% and 55.1% for students. CONCLUSIONS: ConSort is a reliable, valid and sensitive tool for studying static knowledge structure. The applicability of tools that evaluate static knowledge structure should be explored as an addition to existing tools that evaluate dynamic tasks such as diagnostic reasoning.

Alberta↗
PubMed2006

Using a conceptual framework during learning attenuates the loss of expert-type knowledge structure.

BACKGROUND: During evolution from novice to expert, knowledge structure develops into an abridged network organized around pathophysiological concepts. The objectives of this study were to examine the change in knowledge structure in medical students in one year and to investigate the association between the use of a conceptual framework (diagnostic scheme) and long-term knowledge structure. METHODS: Medical students' knowledge structure of metabolic alkalosis was studied after instruction and one year later using concept-sorting. Knowledge structure was labeled 'expert-type' if students shared >or= 2 concepts with experts and 'novice-type' if they shared < 2 concepts. Conditional logistic regression was used to study the association between short-term knowledge structure, the use of a diagnostic scheme and long-term knowledge structure. RESULTS: Thirty-four medical students completed the concept-sorting task on both occasions. Twenty-four used a diagnostic scheme for metabolic alkalosis. Short-term knowledge structure was not a correlate of long-term knowledge structure, whereas use of a diagnostic scheme was associated with increased odds of expert-type long-term knowledge structure (odds ratio 12.6 [1.4, 116.0], p = 0.02). There was an interaction between short-term knowledge structure and the use of a diagnostic scheme. In the group who did not use a diagnostic scheme the number of students changing from expert-type to novice-type was greater than vice versa (p = 0.046). There was no significant change in the group that used the diagnostic scheme (p = 0.6). CONCLUSION: The use of a diagnostic scheme by students may attenuate the loss of expert-type knowledge structure.

Adult↗
PubMed2006

The routine use of high-resolution immunological screening of recipients of primary deceased donor kidney allografts is cost-effective.

BACKGROUND: The economic and health benefits of kidney transplantation are dependent on the length of allograft survival. High-resolution immunological screening can identify recipients at increased risk of early graft loss caused by acute rejection, but the use of these tests increases screening costs before transplantation. The objective of this study was to evaluate the cost-effectiveness of routine use of high-resolution flow-cytometry cross-matching and solid-phase screening for all recipients of primary deceased donor kidney transplants. METHODS: A Markov model was constructed to evaluate costs and effects of two different clinical strategies on a simulated cohort of 1,000 transplant recipients: serological screening (SS) only and flow screening (FS) only. Outcomes measures were total cost of patient care over 25 years, life expectancy, quality-adjusted life expectancy, and transplant life expectancy. RESULTS: In the base-case analysis, FS was associated with an average gain of 0.08 life years, 0.25 transplant life years, and 0.08 quality-adjusted life years per patient. SS was associated with a higher cost of CND$6,397 per patient, mostly because of increased use of dialysis in patients who suffered early graft loss under the SS strategy. The results were robust to uncertainty in the majority of variables, and a strategy using FS was cost-effective except under the unlikely scenario where the false-negative rate for SS was <or=2% or the early graft loss rate for flow-positive recipients was <or=7% (compared with 5% for flow-negative recipients). CONCLUSIONS: Routine use of FS in recipients of first-deceased donor kidney transplants is cost-effective.

Cadaver↗
PubMed2006

Evaluation of a multifaceted "resident-as-teacher" educational intervention to improve morning report.

BACKGROUND: Resident-led morning report is an integral part of most residency programs and is ranked among the most valuable of educational experiences. The objectives of this study were to evaluate the effect of a resident-as-teacher educational intervention on the educational and teaching experience of morning report. METHODS: All senior internal medicine residents were invited to participate in this study as teaching participants. All internal medicine residents and clerks were invited to participate as audience participants. The educational intervention included reading material, a small group session and feedback after teaching sessions. The educational and teaching experiences were rated prior to and three months after the intervention using questionnaires. RESULTS: Forty-six audience participants and 18 teaching participants completed the questionnaires. The degree to which morning report met the educational needs of the audience was higher after the educational intervention (effect size, d = 0.26, p = 0.01). The perceptions of the audience were that delivery had improved and that the sessions were less intimidating and more interactive. The perception of the teaching participants was that delivery was less stressful, but this group now reported greater difficulty in engaging the audience and less confidence in their medical knowledge. CONCLUSION: Following the educational intervention the audience's perception was that the educational experience had improved although there were mixed results for the teaching experience. When evaluating such interventions it is important to evaluate the impact on both the educational and teaching experiences as results may differ.

Adult↗
PubMed2006

Can standardized patients replace physicians as OSCE examiners?

BACKGROUND: To reduce inter-rater variability in evaluations and the demand on physician time, standardized patients (SP) are being used as examiners in OSCEs. There is concern that SP have insufficient training to provide valid evaluation of student competence and/or provide feedback on clinical skills. It is also unknown if SP ratings predict student competence in other areas. The objectives of this study were: to examine student attitudes towards SP examiners; to compare SP and physician evaluations of competence; and to compare predictive validity of these scores, using performance on the multiple choice questions examination (MCQE) as the outcome variable. METHODS: This was a cross-sectional study of third-year medical students undergoing an OSCE during the Internal Medicine clerkship rotation. Fifty-two students rotated through 8 stations (6 physician, 2 SP examiners). Statistical tests used were Pearson's correlation coefficient, two-sample t-test, effect size calculation, and multiple linear regression. RESULTS: Most students reported that SP stations were less stressful, that SP were as good as physicians in giving feedback, and that SP were sufficiently trained to judge clinical skills. SP scored students higher than physicians (mean 90.4% +/- 8.9 vs. 82.2% +/- 3.7, d = 1.5, p < 0.001) and there was a weak correlation between the SP and physician scores (coefficient 0.4, p = 0.003). Physician scores were predictive of summative MCQE scores (regression coefficient = 0.88 [0.15, 1.61], P = 0.019) but there was no relationship between SP scores and summative MCQE scores (regression coefficient = -0.23, P = 0.133). CONCLUSION: These results suggest that SP examiners are acceptable to medical students, SP rate students higher than physicians and, unlike physician scores, SP scores are not related to other measures of competence.

Alberta↗
PubMed2005

Bladder vs enteric drainage in simultaneous pancreas-kidney transplantation.

BACKGROUND: As a valid therapeutic option for patients with type 1 diabetes mellitus (IDDM) and secondary diabetic nephropathy, simultaneous pancreas-kidney (SPK) transplantation remains more undeveloped than other solid organ transplantations due to restrictions of surgical techniques, especially modes of exocrine pancreatic secretion. Enteric drainage (ED) has recently been increasingly popular due to the long-term complications with bladder drainage (BD). Objectives. Compare results of SPK transplants with enteric vs bladder exocrine drainage since the beginning of our experience with this type of transplantation. METHODS: From March 1998 to October 2004, 53 SPK transplants were performed, consisting of 30 with bladder drainage (BD) and 23 with enteric drainage (ED). Induction therapy included antilymphocyte globulin (ALG) or anti-CD25 monoclonal antibody. Maintenance regimen consisted of tacrolimus (TAC)/cyclosporine (CsA), mycophenolate mofetil (MMF) and steroids. RESULTS: Mean age of recipients was 39+/-7 in both groups. No anastomosis leakage occurred in either group. Surgical complications were not significantly different between the two groups. Incidence of acute rejection, major infections and cytomegalovirus disease were also similar. However, the BD group was characterized by a slight increase in number of urologic complications, metabolic acidosis and dehydration. The length of initial hospital stay was likewise comparable. All patients with a functional graft no longer required exogenous insulin. BD actuarial patient survival and graft three-year survival were 96 and 86%, respectively. For ED, the respective results were 97 and 91%, respectively. CONCLUSION: Compared with BD, perioperative morbidity is not increased by ED, and ED is not associated with increased long-term pancreas graft failure. These data suggest that ED is superior to BD and should be considered as the preferred technique for simultaneous pancreas-kidney transplants.

Adult↗
PubMed2005

Does blueprint publication affect students' perception of validity of the evaluation process?

CONTEXT: A major goal of any evaluation is to demonstrate content validity, which considers both curricular content as well as the ability expected of learners. Whether evaluation blueprints should be published and the degree of blueprint transparency is controversial. OBJECTIVES: To examine the effect of blueprint publication on students' perceptions of the validity of the evaluation process. METHODS: This study examined students' attitudes towards the Renal Course evaluation before and after blueprint publication. There was no significant change in the course objectives, blueprint or evaluation between the two time periods. Students' attitudes were evaluated using a questionnaire containing four items related to evaluation. Also collected were the overall course ratings, minimum performance level (MPL) for evaluations and students' performance on each exam. RESULTS: There were no significant differences in the MPL or evaluation scores between the two time periods. A significantly greater proportion of students perceived that the Renal Course evaluation was a fair test and was reflective of both important subject matter and the delivered curriculum. The increased satisfaction process did not appear to be a reflection of their overall satisfaction with the course as there was a trend towards reduced overall satisfaction with the course. CONCLUSIONS: Publication of the evaluation blueprint appears to improve students' perceptions of the validity of the evaluation process. Further studies are required to identify the reasons for this attitude change. We propose that blueprint transparency drives both instructors teaching and student learning towards key educational elements.

Alberta↗
PubMed2005

Use of a minimally invasive donor nephrectomy program to select technique for live donor nephrectomy.

BACKGROUND: Live donor nephrectomy (LDN) is a major surgical procedure with an accepted low mortality and morbidity. Minimally invasive donor nephrectomy (MIDN) has been shown to decrease the wound morbidity associated with the lumbotomy of the classic open technique. Transplant programs face the challenge of initiating their MIDN programs without jeopardizing the safety of the donor and the graft quality. We present the experience at the University of Calgary after the initiation of a MIDN program, with a preoperative selective approach using the 3 major techniques for LDN. METHODS: From December 2001 to May 2004, 50 consecutive, accepted, live kidney donors were evaluated and chosen to undergo nephrectomy by an open, laparoscopic, or hand-assisted technique. Patients were chosen for a particular technique based on the criteria of vascular anatomy, size of abdominal cavity, previous surgery, and technical implications for the recipient. RESULTS: A total of 15 open, 11 laparoscopic, and 24 hand-assisted nephrectomies were performed. There were no statistically significant differences in sex, age, or body mass index between the groups. There were statistically significant differences in surgical times (P < .001) and in the number of days spent in the hospital (P < .001). All kidneys had primary function. There were 2 conversions in the hand-assisted group and 1 blood transfusion in the open group. Death-censored graft survival was 100% with an observation time of 20 months (SD +/- 9 months; range = 3-32 months). One graft from the hand-assisted group was lost from patient death with functioning graft 8 months after transplant. CONCLUSIONS: The learning curve for MIDN does not necessarily need to impact donor or recipient outcomes. The initiation of an MIDN program can be implemented safely if the cases are selected carefully and the use of the classic open technique is kept as an alternative.

Adult↗
PubMed2005

Creating a reliable and valid blueprint for the internal medicine clerkship evaluation.

The objective of this study was to design an examination blueprint for the Internal Medicine clerkship rotation that is congruent with both the learning objectives and delivered learning experiences and reflects the perceived importance of clinical presentations from both the students' and clinicians' perspectives. In this cross-sectional study 11 specialists in General Internal Medicine (GIM) and 11 clinical clerks at the University of Calgary were asked to score each of the 47 clinical presentations in the Internal Medicine clerkship rotation for 'impact' and 'frequency'. These attributes were used to provide an estimate of the relative importance of each clinical presentation. Statistical tests used were the Pearson's correlation coefficient and the Kappa statistic. Multi-attribute utility theory was applied to assess the best way of combining the variables of 'impact' and 'frequency'. The correlation between clerks and GIM specialists was 0.85 for the impact score and 0.86 for the frequency score (p < 0.001 for both). Corresponding Kappa values were 0.71 and 0.82, respectively (p < 0.001 for both). Combining impact and frequency as a multiplicative function produced a distribution that was positively skewed towards common, high impact presentations such as chest pain. We have created an examination blueprint that provides a realistic and objective measure of the relative importance of clinical presentations. Such a blueprint provides both face validity and content validity to the evaluation process.

Alberta↗
PubMed2005

The impact of education on chronic kidney disease patients' plans to initiate dialysis with self-care dialysis: a randomized trial.

BACKGROUND: Compared with in-center hemodialysis, self-care dialysis (including home and self-care hemodialysis and peritoneal dialysis) is less resource intensive and associated with similar clinical outcomes. However, utilization of self-care dialysis has been very low. We performed a randomized controlled trial in predialysis patients with chronic kidney disease (CKD) (GFR <30 mL/min) to determine the impact of a patient-centered educational intervention on patients' intention to initiate dialysis with self-care dialysis. METHODS: Seventy patients with CKD who were receiving care in a multidisciplinary predialysis clinic were randomized to receive either (1) a two-phase patient-centered educational intervention (phase 1 included educational booklets and a 15-minute video on self-care dialysis; phase 2 included a 90-minute small group interactive educational session on self-care dialysis) in addition to their regular multidisciplinary care, or (2) ongoing standard care and education in the multidisciplinary predialysis clinic. The primary outcome was patients' intention to initiate dialysis with self-care dialysis, assessed by questionnaire. RESULTS: Thirty-five patients were randomized to standard care; 34 completed the study. Thirty-five patients were randomized to the educational intervention; 30 completed phase 1 and 28 completed phase 2. By study end, significantly more patients in the intervention group (82.1%) intended to start dialysis with self-care dialysis compared with the standard care group (50%, P= 0.015). This difference persisted after controlling for the small baseline differences among patients in the two study groups (P= 0.004). CONCLUSION: A two-phase educational intervention can increase the proportion of patients who intend to initiate dialysis with self-care dialysis.

Aged↗
PubMed2004

Transplanting kidneys from CMV-seropositive donors to CMV-seronegative recipients is not associated with poorer renal allograft function or survival.

BACKGROUND: Cytomegalovirus (CMV)-seronegative recipients of renal allografts from CMV-seropositive donors (D+/R-) have a higher rate of acute rejection than other renal transplant recipients. A relationship between CMV infection/disease and chronic allograft nephropathy (CAN) has been proposed from animal studies, although human studies have been inconclusive. The objective of this study was to determine if CMV seromatching has an effect on renal allograft function and allograft survival. METHODS: A retrospective single centre study was carried out in 333 first cadaveric transplant recipients from January 1, 1991 to December 31, 1997. The primary end-point was creatinine clearance at 3 years post-transplant in groups based on CMV seromatching. The secondary end-point was renal allograft survival. RESULTS: Mean creatinine clearance 3 years post-transplant was 53.4 ml/min/1.73 m2 of body surface area. There was no significant difference in the mean creatinine clearance for groups formed on the basis of CMV seromatching. Delayed graft function and acute rejection were associated with a lower creatinine clearance at 3 years and reduced overall graft survival [hazard ratios 2.35 (1.56-3.54) (P<0.001) and 1.57 (1.0-2.46) (P = 0.046), respectively]. Considering the end-point of graft loss due to acute rejection (censoring for death with a functioning graft) identified the D+/R- group as having an increased hazard of graft loss due to acute rejection [hazard ratio 3.12 (1.16-8.57) (P = 0.024)]. CONCLUSIONS: The D+/R- group does not appear to have poorer renal allograft function 3 years post-transplant. This group does, however, have an increased risk of early allograft loss due to acute rejection.

Adult↗
PubMed2003

Why patients with ESRD do not select self-care dialysis as a treatment option.

BACKGROUND: In-center hemodialysis is the most prevalent (and resource-intense) form of dialysis in North America despite many patients being capable of performing dialysis themselves. The purpose of this study is to describe reasons in-center hemodialysis patients choose not to perform self-care dialysis and identify variables associated with a negative attitude toward self-care dialysis. METHODS: We conducted a cross-sectional survey (return rate, 83%) of prevalent in-center hemodialysis patients and combined this with demographic and comorbidity data obtained from our prospectively maintained database. We also performed multiple logistic regression to determine factors associated with the attitude, "patients should not perform dialysis without being supervised by a nurse." RESULTS: The most prevalent knowledge barrier was lack of a satisfactory explanation of the various techniques. The most prevalent attitude barriers were that patients should not dialyze without direct supervision, fear of failure to perform self-care dialysis adequately, and fear of social isolation. The most prevalent skill barriers were needle phobia and lack of space at home. Variables significantly associated with a negative attitude toward self-care dialysis were age/fear of substandard care (interaction), needle phobia, fear of change, fear of social isolation, and unwillingness to remain awake during dialysis. CONCLUSION: This study identified a variety of barriers to self-care dialysis, and these results are being used to direct changes to our program aimed at increasing the uptake of self-care hemodialysis, which we believe will benefit both patients and health care providers and may offer a solution to nursing and resource shortages.

Attitude↗
PubMed2003

Analgesic-associated nephropathy in the West of Scotland: a 12-year observational study.

BACKGROUND: Analgesic-associated nephropathy (AAN) is an important and preventable cause of chronic renal failure (CRF). Although its incidence is falling in some countries, others are witnessing an increase in the number of new cases. METHODS: The aim of this study was to evaluate the natural history of AAN, determine the correlates of the rate of decline in renal function and examine factors conferring an increased risk of death or dialysis in such patients. A prospective observational cohort study of all patients with AAN attending a single-centre was conducted. RESULTS: Seventy-eight patients (25 male), with at least 24 months of follow-up for analysis, were diagnosed as having AAN over the 10-year period 1989-1999. During follow up, the mean (+/-SD) rate of change in estimated creatinine clearance (ECC) was -1.2 ml/min/year (+/-5.28). By multiple linear regression three variables were found to independently predict the rate of deterioration in ECC; continuing analgesic use (P < 0.001), degree of proteinuria at presentation (P = 0.002) and male sex (P = 0.03). A Cox's model revealed a 6-fold increase in the hazard of reaching the combined end-point of death or dialysis in those patients with AAN who continue to use analgesics. This was independent of the other two significant risk factors of pre-existing vascular disease (HR 3.93, 1.36-11.29) and ECC at presentation (HR 0.95, 0.91-0.98 per ml/min). CONCLUSIONS: In patients with CRF due to AAN ongoing analgesic use, male gender and increasing proteinuria predict a more rapid decline in renal function. Patients who continue analgesics, those with pre-existing vascular disease and those with more advanced renal impairment at presentation, are at a significantly increased risk of reaching the combined end-point of death or end-stage renal failure requiring dialysis. The design of this study, however, leaves it open to the criticism that selection bias may account for some of its effects, and as with all work on AAN the possible confounding issue of reverse causality is difficult to dismiss.

Aged↗
PubMed2002

Cytomegalovirus seromismatching increases the risk of acute renal allograft rejection.

BACKGROUND: There is an association between cytomegalovirus (CMV) infection or disease and acute allograft rejection in the setting of renal transplantation. There is, however, debate regarding the nature of this association, with evidence supporting both a "forward" relationship (CMV infection or disease precedes acute rejection) and a "backward" relationship (CMV infection or disease follows acute rejection). The objective of this study was to determine whether CMV matching had an independent effect on the risk of acute renal allograft rejection, which would support the view that CMV infection or disease is a risk factor for acute rejection. METHODS: Retrospective single center study (using a prospectively maintained database) of 333 first cadaveric transplant recipients from January 1st 1991 to December 31st 1997. Primary end-point was incidence of acute rejection, diagnosed clinically or by renal biopsy, for different groups formed on the basis of CMV seromatching. RESULTS: One hundred and ninety-four patients (58.3%) had at least one acute rejection episode. CMV seromismatched patients (donor +/recipient-) had a significantly higher rate of acute rejection than non-seromismatched patients (72.6% vs. 54.2%, P=0.005). Using multiple logistic regression, CMV seromismatch, delayed graft function, and biological induction were identified as independent predictors of acute rejection. The adjusted odds ratios for these were 2.28, 1.65, and 0.52, respectively. CONCLUSIONS: Patients who are CMV seromismatched are at higher risk of acute renal allograft rejection. This finding suggests that CMV infection or disease is a risk factor for acute rejection.

Acute Disease↗
PubMed2002

Using "concept sorting" to study learning processes and outcomes.

PURPOSE: First, to evaluate "concept sorting" as a tool for assessing knowledge organization in the memories of first-year medical students, and second, to study the relationship between knowledge organization and examination performance. METHOD: During 2001, first-year medical students taking the Renal Course at the University of Calgary Faculty of Medicine were given a questionnaire on scheme use and were given a concept-sorting task in the domain of metabolic alkalosis. The sophistication of their concept sorting was graded using the number of physiology-based groups they formed. Review of the course's examination scores allowed correlation with concept-sorting scores. Statistical analyses used Fisher's exact test and the two-sample t-test. Pearson's correlation coefficient and the kappa statistic were used for correlation between raters. RESULTS: A total of 81 of 99 students completed the study. The concept-sorting score (mean +/- SEM) for students who used the scheme was higher than was the score for students who did not (2.5 +/- 0.14 versus 1.91 +/- 0.12, p =.016). Students who scored higher in the concept-sorting task, referred to as "deep learners," scored higher than did "surface learners" on exam questions on metabolic alkalosis (2.81 versus 2.29, p =.02). There was no difference in the overall examination performances between the two groups. CONCLUSIONS: Concept sorting may be a useful tool for studying the learning process. Scheme use by students produces a positive outcome on examination performance.

Education, Medical, Undergraduate↗
PubMedDate not supplied

Exacerbation of the ochronosis of alkaptonuria due to renal insufficiency and improvement after renal transplantation.

In alkaptonuria, homogentisate 1,2-dioxygenase deficiency causes tissue accumulation of homogentisic acid (HGA), followed by signs and symptoms of ochronosis. These include massive urinary excretion of HGA, arthritis and joint destruction, pigmentation of cartilage and connective tissue, and cardiac valve deterioration. We describe a 46-year-old man with alkaptonuria and diabetic renal failure whose plasma HGA concentration was twice that of any other alkaptonuria patient, and whose ochronosis progressed much more rapidly than that of his two alkaptonuric siblings. After renal transplantation, the plasma HGA normalized, and the daily urinary excretion of HGA decreased by 2-3g. This case illustrates the critical role of renal tubular secretion in eliminating HGA from the body, and suggests that renal transplantation in a uremic patient not only restores HGA excretion, but may also provide homogentisate 1,2-dioxygenase activity for the metabolism of HGA.

Adult↗