Building toilets and reducing open defecation is the key to significant health benefits for young children in India, a promising study by an Indian-origin researcher shows.

A team of researchers led by Sumeet Patil from School of Public Health, University of California at Berkeley, and the Network for Engineering, Economics Research and Management in Mumbai conducted a randomised trial in 80 rural villages in Madhya Pradesh.

The idea was to measure the effect of India's total sanitation campaign - an initiative to increase access to improved sanitation throughout rural India - on household latrine availability, defecation behaviours and child health.

A total of 5,209 children aged under five years and 3,039 households were involved in the study.

"We found that the campaign intervention increased the percentage of households in villages with improved sanitation facilities by an average of 19 percent," Patil said.

In the intervention villages, an average of 41 percent of households had improved latrines compared to 22 percent of households in the control villages.

The intervention also decreased the proportion of adults who self-reported the practice of open defecation from 84 percent to 73 percent.

"However, the intervention did not improve child health as measured on the basis of multiple health outcomes, including growth, prevalence of gastrointestinal illnesses and anemia," Patil emphasised.

"Despite the limitations of the present study, the results underscore the challenge of achieving large levels of improvements in sanitation to deliver the expected health benefits within the rural sanitation programme," he said.

According to Clarissa Brocklehurst from the Gillings School of Global Public Health at Chapel Hill in North Carolina, "If generations of children are to be saved from stunted growth and ill-health that poor sanitation causes, then addressing sanitation must be one of India's highest priorities".

The study appeared in the journal PLOS Medicine.