Validity of simple approach to scoring and standard setting for standardized-patient cases in an examination of clinical competence.

The results are disappointing, providing little support for the validity of the case-passing decisions based on this simple approach to scoring and standard setting. The case-passing decisions predicted what the case author intended for about only 73% or 74% of the students on average and, with agreement expected by chance removed, predicted what the case author intended for about only 25% of the students. Even with the use of the optimal pass/fail cutoffs and the dropping of students with ambiguous borderline global ratings, the case-passing decisions failed to agree with the case authors' global ratings for 15% to 30% of the students. The findings might be dismissed as simply due to low reliabilities of passing decisions and global ratings based on a single case. Although this concern would apply to intercase reliabilities, which would be subject to case specificity, the appropriate reliabilities here would seem to be intracase (i.e., intrarater), which should be fairly high (if they could be computed). Nevertheless, it seems reasonable to expect much better agreement between results of case scoring and of standard setting developed by the case author and the case author's global ratings of performance on that case, given that the case author might recall the checklist, assign a weight to each item, and so forth. Also, case-passing decisions would possibly agree more with global ratings of live or videotaped performances than with ratings of written summaries of performance; however, that question remains a challenge for further research. In conclusion, the study provides only weak evidence, at best, for the validity of the scoring and standard setting commonly used with SP assessment. The results do not undermine claims about the realism of the SP approach, however, nor do they call into question the standardization afforded by this method of assessing clinical competence. The results do raise serious concerns about this simple approach to scoring and standard setting for SP-based assessments and suggest that we should focus more on the observation and evaluation of actual student performance on SP cases in the development of valid scoring and standard setting.

Hyperbaric oxygen therapy for necrotizing fasciitis reduces mortality and the need for debridements.

Twenty-nine patients with necrotizing fasciitis were treated from 1980 to 1988. This study evaluates how the addition of hyperbaric oxygen (HBO) therapy to surgical treatment has affected mortality and the number of debridements required to achieve wound control in these patients. Two groups of patients were viewed: group 1 (n = 12) received surgical debridement and antibiotics only; group 2 (n = 17) received HBO (90 minutes at 2.5 atm, average 7.4 treatments) in addition to surgery and antibiotics. Both groups were similar in age, race, sex, wound bacteriology, and antimicrobial therapy. Body surface area affected was similar, however, perineal involvement was more common in group 2 (53%) than in group 1 (12%). The admitting conditions of patients in group 1 (non-HBO) were diabetic, 33%; white blood cell count more than 12,000, 50%; and shock, 8%. The admitting conditions of patients in group 2 (HBO) were diabetic, 47%; white blood cell count more than 12,000, 59%; and shock, 29%. Although group 2 patients receiving HBO were more seriously ill on admission, mortality was significantly lower (23%) compared to group 1 (66%) (p less than 0.02). In addition, only 1.2 debridements per group 2 patient were required to achieve wound control versus 3.3 debridements per group 1 patient (p less than 0.03). The addition of HBO therapy to the surgical and antimicrobial treatment of necrotizing fasciitis significantly reduced mortality and wound morbidity (number of debridements) in this study, especially among nonclostridial infections. We conclude that HBO should be used routinely in the treatment of necrotizing fasciitis.

Evaluation of right hemicolectomy for unexpected cecal mass.

Ileocecal mass is occasionally encountered unexpectedly by surgeons operating for presumed appendicitis. A five-year retrospective study was performed to review the management of this problem. Thirteen patients were identified who had had right hemicolectomy performed for unexpected mass in which neoplasm, diverticular disease, or inflammatory bowel disease could not be differentiated from severe appendicitis at laparotomy. Seven patients (group 1) had a final pathologic diagnosis of appendiceal phlegmon. The other patients (group 2) had Crohn's disease, typhlitis, or neoplasm. Right hemicolectomy was performed with a morbidity of 7% and mortality of 7% in all patients. This procedure is acceptable for unexpected cecal mass.

False positive 51Cr release tests during post-transplant immunological monitoring due to recipient serum radioactive contamination.

The occurrence of false positive 51Cr release test results in post-transplant immunological monitoring of human kidney graft recipients due to 131I carryover from renograms is described. False positivity was detected in 7 instances in 4 recipients, and suspected in 12 instances in 7 recipients, in a series of 46 consecutive transplant recipients. Technical methods and controls to detect and prevent such false positivity are described.