Dataset Information

Laboratory Measures as Proxies for Primary Care Encounters: Implications for Quantifying Clinical Retention Among HIV-Infected Adults in North America.

ABSTRACT: Because of limitations in the availability of data on primary care encounters, patient retention in human immunodeficiency virus (HIV) care is often estimated using laboratory measurement dates as proxies for clinical encounters, leading to possible outcome misclassification. This study included 83,041 HIV-infected adults from 14 clinical cohorts in the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) who had ?1 HIV primary care encounters during 2000-2010, contributing 468,816 person-years of follow-up. Encounter-based retention (REB) was defined as ?2 encounters in a calendar year, ?90 days apart. Laboratory-based retention (RLB) was defined similarly, using the dates of CD4-positive cell counts or HIV-1 RNA measurements. Percentage of agreement and the ? statistic were used to characterize agreement between RLB and REB. Logistic regression with generalized estimating equations and stabilized inverse-probability-of-selection weights was used to elucidate temporal trends and the discriminatory power of RLB as a predictor of REB, accounting for age, sex, race/ethnicity, primary HIV risk factor, and cohort site as potential confounders. Both REB and RLB increased from 2000 to 2010 (from 67% to 78% and from 65% to 77%, respectively), though REB was higher than RLB throughout (P < 0.01). RLB agreed well with REB (80%-86% agreement; ? = 0.55-0.62, P < 0.01) and had a strong, imperfect ability to discriminate between persons retained and not retained in care by REB (C statistic: C = 0.81, P < 0.05). As a proxy for REB, RLB had a sensitivity and specificity of 84% and 77%, respectively, with misclassification error of 18%.

SUBMITTER: Rebeiro PF

PROVIDER: S-EPMC4655744 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Laboratory Measures as Proxies for Primary Care Encounters: Implications for Quantifying Clinical Retention Among HIV-Infected Adults in North America.

Rebeiro Peter F PF Althoff Keri N KN Lau Bryan B Gill John J Abraham Alison G AG Horberg Michael A MA Kitahata Mari M MM Yehia Baligh R BR Samji Hasina H Brooks John T JT Buchacz Kate K Napravnik Sonia S Silverberg Michael J MJ Rachlis Anita A Gebo Kelly A KA Sterling Timothy R TR Moore Richard D RD Gange Stephen J SJ

American journal of epidemiology 20151117 11

Because of limitations in the availability of data on primary care encounters, patient retention in human immunodeficiency virus (HIV) care is often estimated using laboratory measurement dates as proxies for clinical encounters, leading to possible outcome misclassification. This study included 83,041 HIV-infected adults from 14 clinical cohorts in the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) who had ≥1 HIV primary care encounters during 2000-2010, contributin ...[more]

PMID: 26578717

Similar Datasets

Project description:BACKGROUND: Although arctic lakes have responded sensitively to 20(th)-century climate change, it remains uncertain how these ecological transformations compare with alpine and montane-boreal counterparts over the same interval. Furthermore, it is unclear to what degree other forcings, including atmospheric deposition of anthropogenic reactive nitrogen (Nr), have participated in recent regime shifts. Diatom-based paleolimnological syntheses offer an effective tool for retrospective assessments of past and ongoing changes in remote lake ecosystems. METHODOLOGY/PRINCIPAL FINDINGS: We synthesized 52 dated sediment diatom records from lakes in western North America and west Greenland, spanning broad latitudinal and altitudinal gradients, and representing alpine (n = 15), arctic (n = 20), and forested boreal-montane (n = 17) ecosystems. Diatom compositional turnover (beta-diversity) during the 20(th) century was estimated using Detrended Canonical Correspondence Analysis (DCCA) for each site and compared, for cores with sufficiently robust chronologies, to both the 19(th) century and the prior approximately 250 years (Little Ice Age). For both arctic and alpine lakes, beta-diversity during the 20(th) century is significantly greater than the previous 350 years, and increases with both latitude and altitude. Because no correlation is apparent between 20(th)-century diatom beta-diversity and any single physical or limnological parameter (including lake and catchment area, maximum depth, pH, conductivity, [NO(3)(-)], modeled Nr deposition, ambient summer and winter air temperatures, and modeled temperature trends 1948-2008), we used Principal Components Analysis (PCA) to summarize the amplitude of recent changes in relationship to lake pH, lake:catchment area ratio, modeled Nr deposition, and recent temperature trends. CONCLUSIONS/SIGNIFICANCE: The ecological responses of remote lakes to post-industrial environmental changes are complex. However, two regions reveal concentrations of sites with elevated 20(th)-century diatom beta-diversity: the Arctic where temperatures are increasing most rapidly, and mid-latitude alpine lakes impacted by high Nr deposition rates. We predict that remote lakes will continue to shift towards new ecological states in the Anthropocene, particularly in regions where these two forcings begin to intersect geographically.

Dataset Information

Laboratory Measures as Proxies for Primary Care Encounters: Implications for Quantifying Clinical Retention Among HIV-Infected Adults in North America.

Publications

Laboratory Measures as Proxies for Primary Care Encounters: Implications for Quantifying Clinical Retention Among HIV-Infected Adults in North America.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets