Fourteen studies were included (8,862 participants). These included one randomised controlled trial (RCT, 118 households including 586 participants), 11 case-control studies (6,588 participants) and two cross-sectional studies (1,688 participants).
One study was classified as high quality, nine as medium quality and three as low quality.
Most studies reported no association between indicators of poor kitchen hygiene and diarrhoeal diseases. The RCT reported no significant difference between kitchen cleaning with a disinfectant and a placebo control in self-reported diarrhoeal disease.
Re-analysis of the UK IID study showed no relationship between most variables and self-reported diarrhoeal diseases.