Table 1 Field activities by country
Country | Angola | Benin | Kenya | Malawi | Mozambique | Senegal | Zambia |
|---|---|---|---|---|---|---|---|
Years | 2011–2014 | 2011–2014 | 2009–2014 | 2009–2013 | 2008–2011 | 2010–2013 | 2012–2014 |
Sites | 4 municipalities in 2 provinces (Kwanza Sul and Uije) | 6 sites | Gem District | Chikhwawa District | 6 sites in Nampula Province (Malema, Chiulo, Ribaue, Quinga, Chinga, Angoche) | 5–6 villages, depending on the number of LLINs available | 4 districts in Luapula Province and 4 districts in Northern Province |
Target nets distributed | 2671 nets | 500 per site (2 sites for retrospective, 4 sites for prospective) | 4505 (attrition) | 3120 (attrition) | 6000 were barcoded, 2023 were found in mapping exercise | 600 per village | 500 each brand, distributed Feb-June 2011 (nets not distributed as part of study) |
Frequency of Follow up | Annual | Every 6 months | Every 6 months | Every 6 months | Annually | Every 6 months | Every 6 months |
Mean Households interviewed at each follow up (range) | 230 (153–307) | 1426 (978–1821) | 3745 (2962–4383) | 2369 (1948–2693) | 214 (198–232) | 1919 (747–3151) | 815 (545–999) |
Average Percentage of nets examined for holes (%) | 48.9 | 51.0 | 13.1a | 7.5a | 69.8 | 69.7 | 78.7 |
Assignment of LLIN brands to sites | Not random | Not random | Randomly assigned to several villages (at least two villages per brand) | Olyset Net was tested in one area only. Other LLIN brands distributed randomly | Not random | 5 LLIN brands tested concurrently in 17 villages | Not random |
Study design | Repeated cross-sections of 50 households per district once per year | Retrospective 2-year-post (2007–2008). Prospective with visits every 6-monthly (2011 on) | Prospective, with surveys every 6 months | Prospective, with surveys every 6 months | Repeated cross-sections of 30 LLINs collected per site once per year | Prospective, with surveys every 6 months | Prospective (each Peace Corps Volunteer followed 25 LLINs for length of study with surveys every 6 months) |
Quantification of hole size | Measurement of long axis to the nearest centimeter; holes < 0.5 cm recorded as < 0.5 cm. 0.5–1 cm recorded as 1 cm | Categories: (I—smaller than a coin); (II—between coin and hand size); (III—larger than a hand); | Length at widest point; distance from bottom of the LLIN | Small (< 2 cm rod), medium (> 2 cm rod, < 9 cm rod), large (> 9 cm rod) | Measurement of long axis to the nearest centimeter; for 0.5–1 cm holes record as 1 cm, for < 0.5 cm record as < 0.5 cm | Counted by size (< 5 cm vs > 5 cm) and placement (top, side, or bottom) | Classified relative to thumb size (0.5–2 cm) |
Laboratory hole counting | Yes | No | Yes | Yes | Yes | Yes | No |