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Zhaojie Wang

Publications and source records attributed to Zhaojie Wang.

2 recordsLinked to original sources

Longitudinal anthropometric changes in HIV-infected and HIV-uninfected men.

BACKGROUND: Although morphologic abnormalities are common among HIV-infected persons receiving highly active antiretroviral therapy (HAART), longitudinal comparative body shape changes among HAART-treated HIV-infected men versus HIV-seronegative men of similar age remain unclear. METHODS: Since September 1999, men enrolled in the Multicenter AIDS Cohort Study underwent body mass index (BMI) and circumference measurements of the waist, hip, thigh, and arm at each semiannual visit. Changes in these measurements that occurred between 1999 and 2003 among HIV-infected men were compared with measurements of HIV-seronegative men using linear mixed effects regression models. The HIV-infected men were further stratified by treatment group (no antiretroviral therapy [ART], monotherapy or combination [mono/combo] ART, or HAART). Analyses were adjusted for age, nadir CD4 cell count, and BMI (for circumference measurements). RESULTS: Over the 4-year observation period, mean BMI increased significantly among the 392 HIV-seronegative men (0.12 kg/m/y; P < 0.001) but did not change in the 3 HIV-infected groups (combined n = 661). Mean waist and hip circumferences increased significantly in all groups. Hip circumferences increased more slowly in the HIV-positive HAART-treated group (n = 488) than in the HIV-seronegative group (0.18 vs. 0.49 cm/y; P < 0.001), however, yielding a more rapid increase in the waist/hip ratio in the HIV-positive, HAART-treated group over time (0.005 per year; P < 0.001). CONCLUSIONS: The increased rate of change in waist/hip ratio in HIV-infected men receiving HAART compared with HIV-seronegative men is attributable to slower increases in hip circumference rather than an increased rate of change in waist circumference. These findings underscore the importance of body fat composition changes in the peripheral compartment relative to the central compartment among HIV-infected men receiving HAART.

Anthropometry↗

Sensitivity analysis of misclassification: a graphical and a Bayesian approach.

PURPOSE: Misclassification can produce bias in measures of association. Sensitivity analyses have been suggested to explore the impact of such bias, but do not supply formally justified interval estimates. METHODS: To account for exposure misclassification, recently developed Bayesian approaches were extended to incorporate prior uncertainty and correlation of sensitivity and specificity. Under nondifferential misclassification, a contour plot is used to depict relations among the corrected odds ratio, sensitivity, and specificity. RESULTS: Methods are illustrated by application to a case-control study of cigarette smoking and invasive pneumococcal disease while varying the distributional assumptions about sensitivity and specificity. Results are compared with those of conventional methods, which do not account for misclassification, and a sensitivity analysis, which assumes fixed sensitivity and specificity. CONCLUSION: By using Bayesian methods, investigators can incorporate uncertainty about misclassification into probabilistic inferences.

Bayes Theorem↗