A comparative study on indicators of vitamin A status and risk factors for sensitivity and specificity of the methods to detect vitamin A deficiency

Table 3 Factors influencing serum retinol accuracy in the assessment of VAD in children 36–59 month of age in rural Burkina Faso

Parameters	Season		CRP		AGP		Helminth infections
Parameters	Dry n = 40	Rainy n = 43	< 5.0 mg/L n = 79	≥ 5.0 mg/L n = 4	< 1.0 g/L n = 58	≥ 1.0 g/L n = 25	Negative n = 40	Positive n = 34
Unadjusted serum retinol
Prevalence of VAD¹	48.9 (34.7; 63.3)	14.0 (6.7; 27.0)	32.2 (23.5; 42.5)	-	29.4 (19.7; 41.5)	34.5 (19.1; 53.9)	39.1 (25.9; 54.2)	24.4 (13.4; 40.2)
Sensitivity²	-	-	-	-	-	-	-	-
Specificity³	52.5	88.4	69.6	-	74.1	64.0	60.0	79.4
Diagnosis accuracy⁴	52.5 (36.8; 67.7)	88.4 (74.4; 95.2)	69.6 (58.5; 78.9)	100	74.1 (61.1; 83.9)	64.0 (42.9; 80.8)	60.0 (43.8; 74.2)	79.4 (61.9; 90.1)
Adjusted Serum retinol
Prevalence of VAD¹	42.5 (29.0; 57.3)	12.0 (5.4; 24.6)	28.0 (19.7; 38.0)	-	29.4 (19.7; 41.5)	20.7 (9.3; 40.0)	32.6 (20.4; 47.7)	21.9 (11.6; 37.6)
Sensitivity²	-	-	-	-	-	-
Specificity³	60.0	90.7	74.7	-	74.1	80.0	67.5	82.4
Diagnosis accuracy⁴	60.0 (43.4; 74.2)	90.7 (77.2; 96.6)	74.7 (63.8; 83.2)	100	74.1 (61.1; 83.9)	80.0 (58.8; 91.8)	67.5 (51.2; 80.4)	82.3 (65.1; 92.1)

CRP, C-reactive protein; AGP, alpha 1-acid glycoprotein; VAD, Vitamin A deficiency; RBP, Retinol binding-protein; TLR, Total liver vitamin A reserves
Values are presented as % (95% Confidence Interval)
¹Dry season, n = 47; Rainy season, n = 50; CRP < 5 mg/L, n = 93; CRP ≥ 5.0 mg/L, n = 4; AGP < 1.0 g/L, n = 68; AGP ≥ 1.0 g/L, n = 29; No helminth, n = 46; Presence of helminths, n = 41
²Sensitivity [True Positive / (True Positive + False Negative)]
³Specificity [True Negative / (False Positive + True Negative)]
⁴Diagnosis accuracy [True Positive + True Negative]

ISSN: 1743-7075