Objectives: The aim of the study was the development and validation of a simple stool diary for caretakers collecting data on stool frequency and consistency among young children in a low-income country.
Methods: Focus group studies evaluated how diarrhea was understood by caregivers (content validity). The sensitivity, reliability, and correlations between dehydration and diary scores (construct validity) were tested in a clinical trial.
Results: Caregivers recognized and understood the concept and severity of diarrhea. Stool frequency and liquid consistency decreased in children admitted with diarrhea (P < 0.0001 for both), confirming good sensitivity of the diary. High reliability was obtained after a few days of training. The caregiver intracorrelation coefficients were 0.66 (0.55-0.77) and 0.75 (0.66-0.84) after 2 and 7 days of training, respectively, and subjective staff evaluation of caregiver scores showed that ≤6% of caregivers had low scoring abilities after 3 days. The degree of dehydration (4-point score) was correlated with both increasing stool frequency and liquid stool consistency (+0.2 points [0.07-0.3], P = 0.0018 for 6 or more diarrheal stools, compared to 3 or more diarrheal stools per day, and +0.5 points (0.3-0.6), P < 0.0001 for diarrheal episodes with 3 or more watery stools/day compared with episodes with 3 or more "watery + abnormally loose + loose" stools per day).
Conclusions: The diary showed high validity, good reliability, and high sensitivity. After 3 days of training, caregivers with mainly no or limited education could report stool consistency with good reliability. Stool consistency, which correlated strongly with dehydration, may be considered an important marker of diarrhea severity in future research.