PovertyDisabled PersonsRisk FactorsUnited StatesTreatment OutcomeHomeless PersonsQuestionnairesRetrospective StudiesAge FactorsCross-Sectional StudiesVisually Impaired PersonsPrevalenceFollow-Up StudiesMentally Ill PersonsCohort StudiesTime FactorsHIV InfectionsMentally Disabled PersonsProspective StudiesIncidenceHealth StatusSocioeconomic FactorsSex FactorsMultivariate AnalysisLongitudinal StudiesPopulation SurveillanceSurvival AnalysisLogistic ModelsPredictive Value of Tests