Impact on diarrhoeal illness of a community educational intervention to improve drinking water quality in rural communities in Puerto Rico

Table 6 comparison in water quality indicators between intervention and non-intervention systems

Parameter	Non-intervention (n = 41)		Intervention (n = 28)		P
	Mean	Standard deviation	Mean	Standard deviation
Turbidity	1.80	2.16	5.18	12.15	0.157^a
pH	7.44	0.41	7.45	0.25	0.834^a
Temp/°C	26.63	1.99	27.13	1.71	0.287^a
Total chlorine	0.21	0.42	0.47	0.72	0.061^a
Free chlorine	0.15	0.36	0.61^c	0.98	0.026^a
	Absent	Present	Absent	Present
Salmonella/L	8	13	6	8	0.778^b
Total coliforms/100 ml	15	25	14	12	0.191^b
E. coli/100 ml	27	13	18	8	0.883^b
Faecal streptococci/100 ml	27	14	15	11	0.501^b '

^a T test
^b Chi squared
^c Mean free chorine higher than mean total chlorine due to missing total chlorine results.

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