In vivo assessment by parents and a physician using the Amsterdam Infant Stool Scale provided better inter-rater agreement than photographic evaluation.

AIM: This study assessed the inter-rater variability of stool assessment, comparing the judgement of parents and a physician using the Amsterdam Infant Stool Scale (AISS) and the evaluation by another physician using photographs.
METHODS: The stools of children aged two to 18 months, who were not toilet-trained, were independently assessed in vivo using the AISS by the parents and the first physician. Another physician, unaware of the results of the in vivo evaluation, assessed two stool photographs taken by the first physician with a smartphone.
RESULTS: Having analysed 100 stools, we found excellent inter-rater agreement between the parents and the first physician for consistency (κ: 0.87; 95% confidence interval [95% CI] 0.78-0.95) and colour (κ: 0.81; 95% CI: 0.71-0.91) and good inter-rater agreement for the amount (κ: 0.79; 95% CI 0.7-0.88). We found moderate inter-rater agreement between the parents' in vivo assessment and the second physician's photographic assessment for stool consistency (κ: 0.5; 95% CI 0.36-0.64) and amount (κ: 0.44; 95% CI 0.29-0.59) and a fair inter-rater agreement for colour (κ: 0.33; 95% CI 0.21-0.45).
CONCLUSION: When parents and a physician used the AISS under in vivo conditions, there was better inter-rater agreement than photographic evaluation by a second physician. ©2016 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.