Table 3.

Data on different algorithms used by ophthalmologists to determine ideal body weight in screening for hydroxychloroquine retinopathy

IBW algorithm	Height (cm)																	Threshold height (cm)	% toxic at 400 mg/d	% with ABW < IBW
	152	155	157	160	163	165	168	170	173	175	178	180	183	185	188	191	193
Wolfe2	45.5	47.7	50.0	52.3	54.5	56.8	59.1	61.4	63.6	65.9	68.2	70.5	72.7	75.0	77.3	79.5	81.8	170	80	10
Met Life women, small frame, mean15	49.5	50.9	52.3	53.6	55.0	56.4	57.7	59.1	60.5	61.8	63.2	64.5	65.9	67.3	68.6	70.0	71.4	175	94	10
Met Life women, large frame, mean15	59.1	60.5	61.8	63.2	65.0	67.3	68.2	69.5	71.4	72.7	74.1	75.5	76.8	78.2	79.5	80.9	82.3	157	16	31
NHLBI table10	55.9	57.7	59.5	61.4	63.6	65.5	67.3	69.5	71.8	73.6	75.9	78.2	80.5	82.7	84.5	87.3	89.5	160	29	27
Bergholz16	58.6	59.5	60.5	61.4	62.3	63.2	64.5	65.5	66.4	67.3	68.2	69.1	70.5	71.4	72.3	73.2	74.1	160	29	27
Michaelides8	44.5	45.9	47.7	49.1	50.9	52.7	54.1	55.9	57.7	59.5	61.4	62.7	64.5	66.4	68.2	70.0	71.8	178	98	5
Walvick7	51.8	53.6	55.0	56.8	58.2	60.0	61.4	63.2	64.5	66.4	67.7	69.5	70.9	72.7	74.1	75.9	77.3	168	70	16

Notes: Values given are ideal body weights in kilograms corresponding to the algorithm of that row and the height of that column. Threshold height, the height at which 400 mg/d hydroxychloroquine exceeds 6.5 mg/kg/d for the ideal body weight algorithm represented on the row being examined. % toxic at 400 mg/d, the percentage of patients below the threshold height based on the sample of patients studied. % with ABW < IBW, the percentage of patients in whom the actual body weight falls below the ideal body weight based on the sample of patients studied.

Abbreviations: ABW, actual body weight; IBW, ideal body weight; Met Life, Metropolitan Life Insurance table for women; NHLBI, National Heart Lung and Blood Institute.