Real Time Versus Photographic Assessment of Stool Consistency Using the Brussels Infant and Toddler Stool Scale: Are They Telling Us the Same?

Purpose: Digital communication is becoming increasingly important in clinical practice and research. The finding that stool consistency can be evaluated similarly using either "in vivo" or photographic material by health care professionals will decrease subjective interpretation by parents. The primary outcome of this study was the reliability of stool consistency scoring using the Brussels Infant and Toddler Stool Scale (BITSS) between fresh stools and their photos; the secondary outcome was the inter-rater reliability based on the fresh stools.

Methods: Fresh stool samples from healthy children were collected in a day care center. These stools, and one month later the corresponding photos presented in a random order, were presented to 14 observers. Reliabilities were analyzed using absolute agreements and weighted and unweighted Cohen's κ.

Results: In total, 202 samples were rated 576 times. Absolute agreement between photographic and real time assessment ranged between 71.1% and 83.3% among observers. This corresponded with substantial agreement (unweighted κ=0.70 [95% CI, 0.61-0.78]; weighted κ=0.86 [95% CI, 0.78-0.88]). The inter-observer agreement showed similar percentages of absolute agreement (81.4-82.0%) and κ-values corresponding with fair-to-moderate agreement.

Conclusion: Our findings suggest that the assessment of fresh stool consistency can also reliably be done on photographic material when using the BITSS. This opens opportunities in scientific surroundings and in our daily life communication with parents and caretakers.