Evaluating the attrition, fabric integrity and insecticidal durability of two dual active ingredient nets (Interceptor® G2 and Royal® Guard): methodology for a prospective study embedded in a cluster randomized controlled trial in Benin

Table 1 Number of Interceptor^® G2, Royal Guard^® and Interceptor^® ITNs to be sampled from Cohort 2 at each timepoint

Months post ITN distribution	No of ITNs to withdrawn for bioefficacy studies	No. of ITN to test in hut trials	No. of ITNs to test in lab bioassays	No. of pieces per ITN	Total number of pieces for bioassays	No. of pieces for chemical analysis^b	ITNs sampled for other studies^c
0	30	–	30	5	150	150
6	30	–	30	4	120	–
12	54^a	54^a	30	4	120	120	80
18	30	-	30	4	120	-
24	54^a	54^a	30	4	120	120	80
30	30	–	30	4	120	–
36	54^a	54^a	50	4	200	200	80
Total	282				950	590	240

^aThese nets will be tested in hut trials prior to laboratory bioassays and chemical analysis. Hut trials will only be performed with nets withdrawn at 12, 24 and 36 months
^bNet pieces preserved for chemical analysis will be obtained from adjacent positions on the same ITNs cut for bioassays
^cThese nets will be samples from cohort 2 nets but will be used in other studies

ISSN: 1475-2875