| Autor: |
Meyer, Ana-Claire L, Boscardin, W John, Kwasa, Judith K, Price, Richard W |
| Rok vydání: |
2013 |
| Předmět: |
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| Zdroj: |
Neuroepidemiology, vol 41, iss 3-4 |
| Popis: |
BackgroundBetween 0 and 48% of normal HIV-uninfected individuals score below threshold neuropsychological test scores for HIV-associated neurocognitive disorders (HAND) or are false positives. There has been little effort to understand the effect of varied interpretations of research criteria for HAND on false-positive frequencies, prevalence and analytic estimates.MethodsThe proportion of normal individuals scoring below Z score thresholds drawn from research criteria for HAND, or false-positive frequencies, was estimated in a normal Kenyan population and a simulated normal population using varied interpretations of research criteria for HAND. We calculated the impact of false-positive frequencies on prevalence estimates and statistical power.ResultsFalse-positive frequencies of 2-74% were observed for asymptomatic neurocognitive impairment/mild neurocognitive disorder and 0-8% for HIV-associated dementia. False-positive frequencies depended on the definition of an abnormal cognitive domain, Z score thresholds and neuropsychological battery size. Misclassification led to clinically important overestimation of prevalence and dramatic decreases in power.ConclusionsMinimizing false-positive frequencies is critical to decrease bias in prevalence estimates and minimize reductions in power in studies of association, particularly for mild forms of HAND. We recommend changing the Z score threshold to ≤-1.5 for mild impairment, limiting analysis to 3-5 cognitive domains and using the average Z score to define an abnormal domain. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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