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Background Diagnosis of a surgical-site infection (SSI) in dermatological surgery can be based entirely on a subjective assessment, according to the fourth criterion of the most common definition of an SSI, which was established by the US Centers for Disease Control and Prevention. Objectives To investigate the interobserver agreement between dermatologists in their diagnosis of SSI of dermatosurgical wounds. Methods An international electronic photographic survey with eight photographs of wounds 1 week after full-thickness skin grafting (FTSG) was sent to dermatologists. All wounds were assessed in terms of visual criteria beforehand. Data collected from respondents included physician characteristics and experience, and SSI assessments of all wounds. Results In total, 393 dermatologists from 27 countries enrolled. Most respondents were from the U.S.A. (25%), followed by Sweden (24%) and the U.K. (13%). There was only a slight interobserver agreement on SSI suspicion (kappa = 0 center dot 19). SSI suspicion was lower for male physicians (P = 0 center dot 03), board-certified dermatologists (P = 0 center dot 001), physicians regularly assessing surgical wounds (P = 0 center dot 03) and physicians performing FTSG (P < 0 center dot 001). Swedish physicians diagnosed more SSIs than U.S. physicians (P = 0 center dot 002). Erythema was more common in cases with higher SSI suspicion. Conclusions This study reveals broad inter-rater variability in the diagnosis of SSI, illustrating the need for novel objective diagnostic methods that can better capture the variables that constitute an SSI.

In many studies, the aim is to learn about the direct exposure effect, that is, the effect not mediated through an intermediate variable. For example, in circulation disease studies it may be of interest to assess whether a suitable level of physical activity can prevent disease, even if it fails to prevent obesity. It is well known that stratification on the intermediate may introduce a so-called posttreatment selection bias. To handle this problem, we use the framework of principal stratification (Frangakis and Rubin, 2002, Biometrics 58, 21-29) to define a causally relevant estimand - the principal stratum direct effect (PSDE). The PSDE is not identified in our setting. We propose a method of sensitivity analysis that yields a range of plausible values for the causal estimand. We compare our work to similar methods proposed in the literature for handling the related problem of "truncation by death." © 2008, The International Biometric Society.

BACKGROUND: Although there is randomized evidence that radical prostatectomy improves survival, there are few data on how benefit varies by baseline risk. OBJECTIVE: We aimed to create a statistical model to calculate the decrease in risk of death associated with surgery for an individual patient, using stage, grade, prostate-specific antigen, and age as predictors. DESIGN, SETTING, AND PARTICIPANTS: A total of 695 men with T1 or T2 prostate cancer participated in the Scandinavian Prostate Cancer Group 4 trial (SPCG-4). INTERVENTION: Patients in SPCG-4 were randomized to radical prostatectomy or conservative management. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Competing risk models were created separately for the radical prostatectomy and the watchful waiting group, with the difference between model predictions constituting the estimated benefit for an individual patient. RESULTS AND LIMITATIONS: Individualized predictions of surgery benefit varied widely depending on age and tumor characteristics. At 65 yr of age, the absolute 10-yr risk reduction in prostate cancer mortality attributable to radical prostatectomy ranged from 4.5% to 17.2% for low- versus high-risk patients. Little expected benefit was associated with surgery much beyond age 70. Only about a quarter of men had an individualized benefit within even 50% of the mean. A limitation is that estimates from SPCG-4 have to be applied cautiously to contemporary patients. CONCLUSIONS: Our model suggests that it is hard to justify surgery in patients with Gleason 6, T1 disease or in those patients much above 70 yr of age. Conversely, surgery seems unequivocally of benefit for patients who have Gleason 8, or Gleason 7, stage T2. For patients with Gleason 6 T2 and Gleason 7 T1, treatment is more of a judgment call, depending on patient preference and other clinical findings, such as the number of positive biopsy cores and comorbidities., Funding Agencies:National Institutes of Health in the United States 1RO1 CA 108746-01A1Prostate Cancer FoundationSidney Kimmel Center for Prostate and Urologic CancersNational Cancer Institute P50-CA92629

Background: The benefit of radical prostatectomy in patients with early prostate cancer has been assessed in only one randomized trial. In 2005, we reported that radical prostatectomy improved prostate cancer survival compared with watchful waiting after a median of 8.2 years of follow-up. We now report results after 3 more years of follow-up. Methods: From October 1, 1989, through February 28, 1999, 695 men with clinically localized prostate cancer were randomly assigned to radical prostatectomy (n = 347) or watchful waiting (n = 348). Follow-up was complete through December 31, 2006, with histopathologic review and blinded evaluation of causes of death. Relative risks (RRs) were estimated using the Cox proportional hazards model. Statistical tests were two-sided. Results: During a median of 10.8 years of follow-up (range = 3 weeks to 17.2 years), 137 men in the surgery group and 156 in the watchful waiting group died (P =. 09). For 47 of the 347 men (13.5%) who were randomly assigned to surgery and 68 of the 348 men (19.5%) who were not, death was due to prostate cancer. The difference in cumulative incidence of death due to prostate cancer remained stable after about 10 years of follow-up. At 12 years, 12.5% of the surgery group and 17.9% of the watchful waiting group had died of prostate cancer (difference = 5.4%, 95% confidence interval [CI] = 0.2 to 11.1%), for a relative risk of 0.65 (95% CI = 0.45 to 0.94, P =. 03). The difference in cumulative incidence of distant metastases did not increase beyond 10 years of follow-up. At 12 years, 19.3% of men in the surgery group and 26% of men in the watchful waiting group had been diagnosed with distant metastases (difference = 6.7%, 95% CI = 0.2 to 13.2%), for a relative risk of 0.65 (95% CI = 0.47 to 0.88, P =. 006). Among men who underwent radical prostatectomy, those with extracapsular tumor growth had 14 times the risk of prostate cancer death as those without it (RR = 14.2, 95% CI = 3.3 to 61.8, P <. 001). Co

BACKGROUND: In 2002, we reported the initial results of a trial comparing radical prostatectomy with watchful waiting in the management of early prostate cancer. After three more years of follow-up, we report estimated 10-year results. METHODS: From October 1989 through February 1999, 695 men with early prostate cancer (mean age, 64.7 years) were randomly assigned to radical prostatectomy (347 men) or watchful waiting (348 men). The follow-up was complete through 2003, with blinded evaluation of the causes of death. The primary end point was death due to prostate cancer; the secondary end points were death from any cause, metastasis, and local progression. RESULTS: During a median of 8.2 years of follow-up, 83 men in the surgery group and 106 men in the watchful-waiting group died (P=0.04). In 30 of the 347 men assigned to surgery (8.6 percent) and 50 of the 348 men assigned to watchful waiting (14.4 percent), death was due to prostate cancer. The difference in the cumulative incidence of death due to prostate cancer increased from 2.0 percentage points after 5 years to 5.3 percentage points after 10 years, for a relative risk of 0.56 (95 percent confidence interval, 0.36 to 0.88; P=0.01 by Gray's test). For distant metastasis, the corresponding increase was from 1.7 to 10.2 percentage points, for a relative risk in the surgery group of 0.60 (95 percent confidence interval, 0.42 to 0.86; P=0.004 by Gray's test), and for local progression, the increase was from 19.1 to 25.1 percentage points, for a relative risk of 0.33 (95 percent confidence interval, 0.25 to 0.44; P<0.001 by Gray's test). CONCLUSIONS: Radical prostatectomy reduces disease-specific mortality, overall mortality, and the risks of metastasis and local progression. The absolute reduction in the risk of death after 10 years is small, but the reductions in the risks of metastasis and local tumor progression are substantial.