Table 1.

Included studies of point-of-use chlorine water treatment with reported adoption, by product type.

Product type	Reference	Setting	Study design	Enrolled households (or other specified unit) ($n$)a	Indicator of adoption	Last measured adoption (%)	Time point at measurement	Change in adoption ($+/-/=$)b
Flocculant–disinfectant	Albert et al. (b)35c	Kenya (rural)	RCT (crossover)	400	Self-report	62	2 months	NA
Flocculant–disinfectant	Chiller et al.38 and Luby et al.37	Guatemala (rural)	RCT	268	FCR $>0.1\mathrm{mg}/\mathrm{L}$	44 and 1.5	10 wk and 8.5 months	−
Flocculant–disinfectant	Colindres et al.61	Haiti (rural)	Cross-sectional study	100	FCR $\ge 0.1\mathrm{mg}/\mathrm{L}$	12	1 month	NA
Flocculant–disinfectant	Crump et al. (a)41c	Kenya (rural)	cRCT	201 family compounds	FCR $>0.1\mathrm{mg}/\mathrm{L}$	44	Pooled (5 months)	NA
Flocculant–disinfectant	Doocy and Burnham55	Liberia (IDP camp)	cRCT	200	FCR $\ge 0.1\mathrm{mg}/\mathrm{L}$	95	Pooled (12 wk)	NA
Flocculant–disinfectant	Geremew et al. (b)36c	Ethiopia (rural)	cRCT (crossover)	400	Detectable free chlorine	25	2 months	$=$
Flocculant–disinfectant	Luoto et al. (c)42	Bangladesh (urban)	RCT (crossover)	600	Detectable free chlorine	3	6 weeks	NA
Flocculant–disinfectant	Norton et al.64	Bangladesh (rural)	Nonrandomized trial	105 women	FCR $>0.2\mathrm{mg}/\mathrm{L}$	43	Pooled (12 wk)	NA
Flocculant–disinfectant	Rangel et al. (b)44c	Guatemala (rural)	RCT	60	FCR $\ge 0.5\mathrm{mg}/\mathrm{L}$	83	Pooled (3 wk)	NA
Flocculant–disinfectant	Reller et al. (b)45c	Guatemala (rural)	RCT	199	FCR $>0.1\mathrm{mg}/\mathrm{L}$	30	Pooled (9 months)	NA
Flocculant–disinfectant	Shaheed et al. (a)46c	Pakistan (rural)	RCT (crossover)	247	Total chlorine $\ge 0.2\mathrm{mg}/\mathrm{L}$	59	8 wk	−
Flocculant–disinfectant	Shaheed et al. (b)46c	Zambia (urban)	RCT (crossover)	214	Total chlorine $\ge 0.2\mathrm{mg}/\mathrm{L}$	18	8 wk	−
Liquid	Albert et al. (a)35c	Kenya (rural)	RCT (crossover)	400	Self-report	76	2 months	NA
Liquid	Crump et al. (b)41c	Kenya (rural)	cRCT	203 family compounds	FCR $>0.1\mathrm{mg}/\mathrm{L}$	61	Pooled (5 months)	NA
Liquid	Geremew et al. (a)36c	Ethiopia (rural)	cRCT (crossover)	400	Detectable free chlorine	41	2 months	$=$
Liquid	Humphrey et al.9	Zimbabwe (rural)	cRCT	2,035 womend	FCR $>0.1\mathrm{mg}/\mathrm{L}$	58	12 months	NA
Liquid	Luby et al.82	Pakistan (urban)	Trial (unclear if randomized)	50	FCR $>0.1\mathrm{mg}/\mathrm{L}$	71	Pooled (10 wk)	NA
Liquid	Luoto et al. (a)42c	Bangladesh (urban)	RCT (crossover)	600	Detectable free chlorine	11	6 wk	NA
Liquid	Macy and Quick83	Nicaragua (rural)	Nonrandomized trial	100	FCR $>0.1\mathrm{mg}/\mathrm{L}$	52	3 months	NA
Liquid	Mellor et al.53	Guatemala (rural)	RCT	34	FCR $\ge 0.2\mathrm{mg}/\mathrm{L}$	65	7 months	−
Liquid	Mengistie et al.84	Ethiopia (rural)	cRCT	286	FCR $\ge 0.2\mathrm{mg}/\mathrm{L}$	77	12 wk	$=$
Liquid	Murray et al.57	Haiti (peri-urban)	Nonrandomized trial	60	FCR $>0.1\mathrm{mg}/\mathrm{L}$	13	13 months	−
Liquid	Null et al.8	Kenya (rural)	cRCT	2,737	Detectable free chlorine	21	2 y	−
Liquid	Opryszko et al.48	Afghanistan (rural)	cRCT	607	Self-report	80	1 y	NA
Liquid	Potgieter et al. (a)43c	South Africa (rural)	RCT	20	Detectable free chlorine	88	3 months	$=$
Liquid	Potgieter et al. (b)43c	South Africa (rural)	RCT	20	Detectable free chlorine	98	3 months	$+$
Liquid	Quick et al.49	Bolivia (urban)	RCT	15	FCR $\ge 0.1$	100	9 wk	$=$
Liquid	Quick et al.51	Bolivia (peri-urban)	RCT	64	Detectable total chlorine	95	6 months	$+$
Liquid	Quick et al.50	Zambia (peri-urban)	Nonrandomized trial	166	Detectable total chlorine	85	13 wk	$+$
Liquid	Rangel et al. (a)44c	Guatemala (rural)	RCT	20	FCR $\ge 0.5\mathrm{mg}/\mathrm{L}$	83	Pooled (3 wk)	NA
Liquid	Reller et al. (a)45c	Guatemala (rural)	RCT	197	FCR $>0.1\mathrm{mg}/\mathrm{L}$	40	Pooled (9 months)	NA
Liquid	Sobsey et al. (a)47c	Bangladesh (urban)	RCT	$\sim 138$	Detectable free chlorine	89	Pooled (8 months)	NA
Liquid	Sobsey et al. (b)47c	Bolivia (peri-urban)	RCT	$\sim 70$	Detectable free chlorine	77	Pooled (6 months)	NA
Liquid	Solomon et al.85	Ethiopia (rural)	cRCT	203	FCR $\ge 0.2\mathrm{mg}/\mathrm{L}$	81	Pooled (4 months)	NA
Liquid	Sugar et al.52	Kenya (urban)	Program evaluation	392 children	Smell of chlorine	97	Pooled (12 months)	NA
Tablet	Altmann et al.56	Chade	cRCT	850 children	FCR $\ge 0.1\mathrm{mg}/\mathrm{L}$	98	2 months	$=$
Tablet	Boisson et al.62	India (urban/rural)	RCT	1,080	FCR $\ge 0.1\mathrm{mg}/\mathrm{L}$	47	12 months	$+$
Tablet	Clasen et al.54	Bangladesh (urban)	RCT	50	FCR $\ge 0.1\mathrm{mg}/\mathrm{L}$	100	4 months	$=$
Tablet	Ercumen et al.86	Bangladesh (rural)	RCT	600	FCR $\ge 0.2\mathrm{mg}/\mathrm{L}$	79	1 y	−
Tablet	George et al. (a)39	Bangladesh (urban)	cRCT	84	FCR $\ge 0.2\mathrm{mg}/\mathrm{L}$	94	Pooled (9 d)	NA
Tablet	Jain et al.60	Ghana (peri-urban)	RCT	120	FCR $\ge 0.2\mathrm{mg}/\mathrm{L}$	83	12 wk	$=$
Tablet	Luby et al.7	Bangladesh (rural)	cRCT	2,086 compounds	FCR $>0.1\mathrm{mg}/\mathrm{L}$	84	2 y	$=$
Tablet	Luoto et al. (b)42	Bangladesh (urban)	RCT (crossover)	600	Detectable free chlorine	10	6 wk	NA
Tablet	Pickering et al.59	Bangladesh (urban)	cRCT	90	Total chlorine $>0.1\mathrm{mg}/\mathrm{L}$	55	10 months	−
Multiple	Blanton et al.58	Kenya (rural)	Program evaluation	662	FCR $\ge 0.1\mathrm{mg}/\mathrm{L}$	18	13 months	$=$
Granular	Tsai et al.63	Haiti (rural)	cRCT	447	FCR $\ge 0.5\mathrm{mg}/\mathrm{L}$	27	180 d	−

Note: Flocculant–disinfectant products included PuR, PureIt, Purifier of Water, and Bishan Gari (local brand in Ethiopia). Liquid chlorine products included sodium hypochlorite, WaterGuard, Klorin/Clorin, bleach, calcium hypochlorite solution, and electrochlorinator (for at-home sodium hypochlorite production). Tablet chlorine products included Aquatabs. Multiple products in a single study included PuR and WaterGuard. Granular chlorine products included Klorfasil. cRCT, cluster randomized controlled trial; FCR, free chlorine residual; IDP, internally displaced persons; NA, not applicable; RCT, randomized controlled trial.

^a Sample size was included for chlorine arm(s) only.

^b Change in adoption: $+\text{indicates}$ $\ge 10\text{\hspace{0.17em}percentage}$ point increase from first to last measure; – indicates $\ge 10\text{\hspace{0.17em}percentage}$ point decrease; $=\text{indicates}$ $<10\text{\hspace{0.17em}percentag}\text{e}$ point change.

^c Albert et al.,³⁵ Crump et al.,⁴¹ Geremew et al.,³⁶ Shaheed et al.,⁴⁶ Luoto et al.,⁴² Potgieter et al.,⁴³ Rangel et al.⁴⁴ Reller et al.,⁴⁵ and Sobsey et al.⁴⁷ had multiple eligible chlorine intervention arms that are separately listed because they had different settings or chlorine products. Separate arms (referred to here as intervention groups) are indicated with letters in parentheses. We combined intervention arms with the same product, even if other intervention components differed. Studies in which measurement across multiple time points are presented as a pooled statistic are indicated as such, with the study duration in parentheses.

^d FCR was measured in only 752 households; self-reported adoption across the entire sample was 87%.

^e Urban, rural, or peri-urban was not specified and could not be inferred from the main text of the paper.