Impact of improvement of water supply on household economy in a squatter area of Manila

Improvements in water supply enhance household economy as residents are able to reallocate time saved in collecting water to income-generating activities.

“A further impact evaluation concluded that improvements in water supply enhance household economy as residents are able to reallocate the time saved in collecting water to income‐generating activities (Aiga 2002).”

Previous water collection time constrained income generating activities.

“Previous water collection time constrained income generating activities.”

Rainwater collection was not considered a suitable option for domestic water use.

“Rainwater collection was not considered a suitable option for domestic water use.”

Financial burden of water had been reduced by the improvement of water supply, and the appropriate level of financial burden of loan repayment on the household economy had encouraged the residents (particularly those formerly in charge of water collection) to work for income.

“Financial burden of water had been reduced by the improvement of water supply, and the appropriate level of financial burden of loan repayment on the household economy had encouraged the residents (particularly those formerly in charge of water collection) to work for income ( Aiga 2002 )”

Most control residents in charge of water collection expressed their willingness to work for additional income when water supply improved.

“Most control residents in charge of water collection expressed their willingness to work for additional income when water supply improved ( Aiga 2002 )”

Poor water availability restricted water consumption and impacted slum residents' financial situation, owing to the expenses involved in acquiring water and reduction of work opportunities.

“Poor water availability restricted water consumption and impacted slum residents' financial situation, owing to the expenses involved in acquiring water and reduction of work opportunities ( Aiga 2002 )”

Households used expensive water delivery services or designated one household member responsible for water collection, due to long collection times.

“Households used expensive water delivery services or designated one household member responsible for water collection, due to long collection times ( Aiga 2002 )”

The majority of men, women and boys stated that the main benefit of the regular water supply was the time saved.

“The majority of men, women and boys stated that the main benefit of the regular water supply was the time saved ( Aiga 2002 )”

Most households collected water from public water faucets.

“Most households collected water from public water faucets.”

Cattaneo 2009 selected controls using propensity score matching and adjusted for confounders, while Aiga 2002 and Moraes 2004 controlled for potential confounders.

“Cattaneo 2009 selected controls using propensity score matching and adjusted for confounders whilst two studies controlled for potential confounders (Aiga 2002; Moraes 2004).”

Only one supporting study (Cattaneo 2009) was judged to have a mixed or unclear risk of bias; the remaining eight supporting studies were all judged to have a high risk of bias (Abelson 1996; Aiga 2002; De Leon 1986; Joshi 2002; Milone 1993; Moitra 1987; Moraes 2004; Parikh in press).

“Only one supporting study was judged to have a mixed or unclear risk of bias (Cattaneo 2009), the remaining eight studies were all judged to have a high risk of bias (Abelson 1996; Aiga 2002; De Leon 1986; Joshi 2002; Milone 1993; Moitra 1987; Moraes 2004; Parikh in press).”

Nine supporting studies were included: six CPI studies (Aiga 2002; Cattaneo 2009; De Leon 1986; Moitra 1987; Moraes 2004; Parikh in press) and three UBA studies (Abelson 1996; Joshi 2002; Milone 1993).

“Nine supporting studies were included: six CPI studies (Aiga 2002; Cattaneo 2009; De Leon 1986; Moitra 1987; Moraes 2004; Parikh in press) and three UBA studies (Abelson 1996; Joshi 2002; Milone 1993).”

Except for three supporting studies (Aiga 2002; De Leon 1986; Joshi 2002), the majority were clustered, yet four studies did not adjust for the clustering effect (Abelson 1996; Milone 1993; Moitra 1987; Moraes 2004).

“Except for three (Aiga 2002; De Leon 1986; Joshi 2002), the majority of studies were clustered yet four studies did not adjust for the clustering effect (Abelson 1996; Milone 1993; Moitra 1987; Moraes 2004).”

Global agencies commonly provided financial assistance, including the World Bank (Aiga 2002), Asian Development Bank (Milone 1993), UK government overseas departments (Abelson 1996), and United Nations (De Leon 1986).

“Global agencies commonly provided financial assistance, including the World Bank (Aiga 2002), Asian Development Bank (Milone 1993), UK government overseas departments (Abelson 1996) and the United Nations (De Leon 1986).”

Aiga 2002 studied the impact of improvement of water supply on diarrhoea and household economy, but water improvements were taking place in the context of a multicomponent ZIP including water connections, private toilets, electric power supplies to every housing unit, paved roadways, and secure tenure.

“Aiga 2002 studied the impact of improvement of water supply on diarrhoea and household economy. However, closer examination of the article revealed that water improvements were taking place in the context of a multicomponent ZIP including water connections, private toilets, electric power supplies to every housing unit, paved roadways and secure tenure.”

The remaining supporting studies (Abelson 1996; Aiga 2002; Milone 1993; Moitra 1987; Moraes 2004; Parikh in press) did not clearly report the follow-up period following intervention delivery.

“The remaining studies did not clearly report the follow‐up period following the intervention delivery (Abelson 1996; Aiga 2002; Milone 1993; Moitra 1987; Moraes 2004; Parikh in press).”

Aiga 2002 did not formally evaluate fidelity but described residents in the intervention enjoying water nearly 24 hours per day.

“Aiga 2002 did not formally evaluate fidelity but described residents in the intervention enjoying water nearly 24 hrs per day.”

Aiga 2002 did not discuss the fidelity of additional interventions delivered as part of the zonal improvement programme (ZIP), which may also have been factors responsible for the outcomes observed.

“The study did not discuss the fidelity of the additional interventions delivered as part of the zonal improvement programme (ZIP), which may also have been factors responsible for the outcomes observed.”

Two supporting studies (Aiga 2002; Moraes 2004) emphasised one aspect of a slum upgrading strategy without detailed consideration of co-interventions.

“Two supporting studies emphasised one aspect of a slum upgrading strategy being implemented without detailed consideration of co‐interventions.”

In Aiga 2002, lower diarrhoeal incidence among children under five years was associated with the presence of multicomponent slum upgrading (RR 0.29, 95% CI 0.20 to 0.42; P<0.0001).

“Lower diarrhoeal incidence among children under five years was associated with the presence of the multicomponent slum upgrading (RR 0.29; 95% CI 0.20 0.42; P < 0.0001) in one CPI (Aiga 2002).”

Only one study (Aiga 2002) reported a power calculation to identify the required sample size for detecting significant effects.

“Only one study reported a power calculation to identify the required sample size for detecting significant effects (Aiga 2002).”

In Aiga 2002, mean proportion of monthly income spent on water was 2.8% in intervention slum compared to 10.1% in control slum (reported P<0.05).

“Mean proportion of monthly income spent on water in intervention versus control households 2.8% in intervention slum compared to 10.1% in control slum, reported P<0.05.”

Five studies (three CPIs and two UBAs) found that multicomponent physical slum upgrading was associated with improved income (Abelson 1996; Aiga 2002; Joshi 2002; Moraes 2004; Parikh in press).

“In contrast, five studies (three CPIs and two UBAs) found that multicomponent physical slum upgrading was associated with improved income (Abelson 1996; Aiga 2002; Joshi 2002; Moraes 2004; Parikh in press).”

In Aiga 2002, mean monthly water expenditure was 109 versus 234 peso/household/month in intervention compared to control households (reported P<0.01).

“Mean monthly water expenditure in intervention compared to control households 109 versus 234 peso/household/month. Reported P<0.01. Multicomponent slum upgrading 401 households. ( Aiga 2002 CPI +/‐)”

In Aiga 2002, households living below the poverty threshold in intervention group compared to control had RR 0.47 (95% CI 0.37 to 0.59; P<0.001).

“Households living below the poverty threshold in intervention group compared to control. RR = 0.47 (95% CI 0.37 to 0.59; P<0.001) Multicomponent slum upgrading 401 households. ( Aiga 2002 CPI +/‐)”

In Aiga 2002, mean adjusted household income per capita was 1563 vs. 1130 pesos/person/month in intervention versus control (reported P<0.05).

“Mean adjusted household income per capita, intervention versus control 1563 vs. 1130 pesos/person/month, Reported P‐Value <0.05 Multicomponent slum upgrading 401 households. ( Aiga 2002 CPI +/‐)”

In one CPI, mean water expenditure and mean proportion of income spent on water were lower in the intervention group receiving improved water supply as part of multicomponent slum upgrading than in the control group (109 vs 234 peso/household/month, P < 0.01; 2.8% vs 10.1%, P < 0.05) (Aiga 2002).

“Mean water expenditure and mean proportion of income spent on water was lower in the intervention group who received improved water supply as part of multicomponent slum upgrading, than the control group (109 peso/household/months in the intervention slum compared to 234 peso/household/month in control slum, P < 0.01; and 2.8% in the intervention slum compared to 10.1% in the control slum, P < 0.”

In Aiga 2002, water delivery services were utilised by 39% of households at a price four times as expensive as the unit price of water itself, to overcome long water collection waiting times.

“Water delivery services were utilised by 39% of households used at a price four times as expensive as the unit price of water itself, to overcome long water collection waiting times (Aiga 2002).”

Infrastructure was believed to free time which could be used for productive activities (such as income generating opportunities or school) (Aiga 2002; Milone 1993; Parikh in press).

“Infrastructure was believed to free time which could be used for productive activities (such as income generating opportunities or school) (Aiga 2002; Milone 1993; Parikh in press).”

In Aiga 2002, all participants in the intervention focus group discussions unanimously agreed that the financial burden of water had been reduced by the improvement of water supply.

“All participants in the intervention focus group discussions unanimously agreed that the financial burden of water had been reduced by the improvement of water supply (Aiga 2002).”

Water supply was perceived to reduce financial burden (Aiga 2002; Parikh in press).

“Water supply was perceived to reduce financial burden (Aiga 2002; Parikh in press).”

Aiga 2002 found that households in the slum receiving multicomponent upgrading were less likely than controls to be living under the poverty threshold (RR 0.47; 95% CI 0.37 to 0.59; P < 0.001 based on income levels).

“Aiga 2002, a CPI study, found that households in the slum receiving multicomponent upgradrading were less likely than controls to be living under the poverty threshold (RR 0.47; 95% CI 0.37 to 0.59; P < 0.001 based on income levels).”

In Aiga 2002, 68.6% of the 122 household members in charge of water collection expressed their willingness to work for additional income when water supply is improved.

“A total of 68.6% of the 122 household members in charge of water collection expressed their willingness to work for additional income when water supply is improved (Aiga 2002).”

Four supporting studies with high risk of bias reinforced the result that lower diarrhoea incidence was associated with receiving a single cement flooring intervention (Cattaneo 2009) or multicomponent slum upgrading (Aiga 2002; Milone 1993; Moraes 2004).

“Four supporting studies with high risk of bias reinforced this result, reporting that lower diarrhoea incidence was associated with receiving a single cement flooring intervention (Cattaneo 2009) or multicomponent slum upgrading (Aiga 2002; Milone 1993; Moraes 2004).”

Residents mentioned less days lost to illness, fewer back problems from carrying water, increases in feeling energetic and saving time from water collection that was directed to income generating opportunities.

“Residents mentioned less days lost to illness, fewer back problems from carrying water, increases in feeling energetic and saving time from water collection that was directed to income generating opportunities (Aiga 2002; Parikh in press).”

The additional time allowed for productive activities such as school or income generating opportunities.

“The additional time allowed for productive activities such as school (Parikh in press) or income generating opportunities (Aiga 2002).”

Access to safe water and sanitation was described as freeing time, for example from collecting water and as a result of fewer days lost to illness.

“Access to safe water and sanitation was described as freeing time (Aiga 2002; Joshi 2002; Parikh in press) for example from collecting water (Aiga 2002) and as a result of fewer days lost to illness (Parikh in press).”

Views and opinions of slum dwellers collected in only five supporting studies offer potential reasons for why slum upgrading strategies may improve health and wellbeing.

“Views and opinions of slum dwellers collected in only five supporting studies (Aiga 2002; De Leon 1986; Joshi 2002; Milone 1993; Parikh in press) offer potential reasons for why slum upgrading strategies may improve health and wellbeing.”

Slum dwellers described less costs for medical expenses as a result of less illness, and the financial burden of accessing water was reduced by improvement of water supply.

“Slum dwellers described less costs for medical expenses as a result of less illness (Parikh in press), and the financial burden of accessing water was reduced by improvement of water supply (Aiga 2002).”

Multicomponent physical environment and infrastructure interventions without other living environment interventions were evaluated in one main study and four supporting studies.

“Multicomponent physical environment and infrastructure interventions without other living environment interventions were evaluated in one main study (Soares 2005) and four supporting studies (Aiga 2002; Milone 1993; Moraes 2004; Parikh in press).”

Slum upgrading interventions included secure tenure or time‐bound guarantees from threat of eviction were described in over half of the supporting studies.

“Slum upgrading interventions included secure tenure or time‐bound guarantees from threat of eviction were described in over half of the supporting studies (Abelson 1996; Aiga 2002; De Leon 1986; Joshi 2002; Moraes 2004; Parikh in press).”

Propensity score matching was utilised by Cattaneo 2009 and effect estimates were controlled for potential confounders in three studies to try to minimise such bias.

“Propensity score matching was utilised by Cattaneo 2009 and effect estimates were controlled for potential confounders in three studies (Aiga 2002; Cattaneo 2009; Moraes 2004) to try to minimise such bias.”

The studies were mostly CPI designs that lacked baseline data and were highly susceptible to selection bias.

“The studies were mostly CPI designs that lacked baseline data (Aiga 2002; Cattaneo 2009; De Leon 1986; Moitra 1987; Moraes 2004; Parikh in press) and were highly susceptible to selection bias.”