Table 5.

Quality assessment of the case-control studies.

Study (year)	Same study base comparisons?	Control for confounding	Comparable accuracy	Ref.
Canteyet al. (2005)	Not clear if cases and controls came from the same study base	Matched on CD4 category Conditional logistic regression during analysis	Not clear if the same tests were performed to establish diagnosis for the cases and controls Unable to collect complete data on the dose and duration of antifungal treatment prior to study recruitment	[30]
Kris et al. (1999)	Cases and controls came from the same study base	Matched based on year of enrollment and length of follow-up Inclusion required CD4 cell count <250 cells/mm3 for both cases and controls Conditional logistic regression was used for other confounders during analysis	Diagnosis of CCM required positive tests for the cases Any control complaining of features similar to cryptococcal meningitis had lumbar puncture and tests on CSF performed to rule out fungal infection	[31]
Quagliarello et al. (1995)	Cases and controls came from the same study base	Matched according to age, sex and time of lumbar puncture Inclusion required: CD4 <250 cells/mm3, lumbar puncture and CSF culture, follow-up of 6 months before lumbar puncture Conditional logistic regression was done to adjust for unmatched confounders	Patient eligibility was determined without knowledge of drug history Similar tests were conducted for both cases and controls (CD4 cell count, lumbar puncture and CSF tests)	[32]
Ammassariet al. (1995)	Cases and controls came from the same study base	Matched according to presence or absence of AIDS-defining event, CD4 cell count, date of CD4 testing Inclusion required: documented HIV infection, follow-up of 1 year before matching Conditional logistic regression was used to adjust for unmatched confounders	For cases, diagnosis of cryptococcal meningitis required positive CSF cultures and CRAG tests Exposure to fluconazole (dose, duration) for both cases and controls was established by checking prescriptions in the patient clinical records	[34]

CCM: Cryptococcal meningitis; CRAG: Cryptococcal antigen; CSF: Cerebrospinal fluid.