Quality of data collection in a large HIV observational clinic database in sub-Saharan Africa: implications for clinical research and audit of care

Table 2 Number and incidence rates of opportunistic infections in the initial 24 months after ART initiation, and percent underreporting of OI events in routine clinic versus research cohort databases for: (Comparison A) 559 patients in research cohort and same 559 patients in routine clinic databases; and (Comparison B) 559 patients in research cohort database versus 1233 patients in routine clinic database

	Research cohort database (n = 559)		Routine clinic database (n = 559)		Routine clinic database (n = 1233)		% underreporting of OI events in 559 patients in routine clinic vs. research cohort database (Comparison A)		% underreporting of OI events in 1233 patients in routine clinic vs. research cohort database (Comparison B)
Type of OI	No. of OI events	Incidence rate (95% CI (per 100 PYAR)	No. of OI events	Incidence rate (95% CI (per 100 PYAR)	No. of OI events	Incidence rate (95% CI (per 100 PYAR)	Based on absolute number of OI events	Based on OI rates	Based on OI rates
Overall (initial OI only)	154^a	24.1 (20.5- 28.2)	91^a	13.2 (10.8 - 16.2)	206^a	10.4 (9.1 - 11.9)	40.9	45.2	56.8
Oral candidiasis	63	8.4 (6.5 - 10.7)	26	3.7 (2.5 - 5.4)	54	2.6 (2.0 - 3.3)	58.7	55.9	69.0
Severe bacterial pneumonia	44	5.5 (4.1 - 7.6)	8	1.0 (0.5 - 2.1)	4	0.2 (0.1 - 0.5)	81.8	81.8	96.4
Tuberculosis	33	4.1 (2.9 - 5.8)	27	3.6 (2.5 - 5.3)	73	3.6 (2.8 - 4.5)	18.2	12.2	12.2
Herpes zoster	29	3.6 (2.5 - 5.2)	5	0.6 (0.3 - 1.3)	9	0.4 (0.2 - 0.8)	82.7	83.3	88.8
Cryptococcus meningitis	7	0.8 (0.4 - 1.8)	7	0.9 (0.4 - 1.9)	16	0.7 (0.4 - 1.2)	0	+12.5 ^b	12.5
Genital herpes	5	0.6 (0.2 - 1.4)	15	2.0 (1.2 - 3.3)	12	0.5 (0.3 - 1.0)	+200 ^b	+233^b	16.7
Kaposi's sarcoma	5	0.6 (0.2 - 1.4)	5	0.6 (0.3 - 1.6)	31	1.5 (1.1 - 2.2)	0	+16.7 ^b	+150 ^b
Oesophageal candidiasis	5	0.6 (0.2 - 1.4)	0	0.0 (0.0 - 0.0)	4	0.2 (0.1 - 0.5)	100	100	66.7
Cerebral toxoplasmosis	2	0.2 (0.1 - 0.9)	0	0.0 (0.0 - 0.0)	4	0.2 (0.1 - 0.5)	100	100	0
Other OIs^c	8	0.9 (0.5 - 1.9)	3	0.4 (0.1 - 1.2)	11	0.5 (0.3 - 0.9)	62.5	55.5	44.4

a represents the total number of initial OI events only. In the research cohort database of 559 patients, there were 154 initial OIs, but a total of 204 events, as 116 had one OI, 28 had two OI events, and 10 had three or more OIs. In routine clinic database of 559 patients, there were 91 initial OIs, but at total of 100 events, as 87 had one OI, seven had two OI events, and one patient had three OIs. In routine clinic database of 1233 patients, there were 206 initial OIs, but a total of 224 events, as 188 had one OI, 16 had two OI events, and two patients had three OIs.)
b OIs where there were more events reported in the clinic versus research database, representing underreporting in the research database.
c Other OIs includes Pneumocystis jirovecii pneumonia, CMV retinitis, lymphoma, HIV-related anaemia, septicaemia, chronic diarrhoea, intracerebral mass, and pulmonary aspergillosis.