Introduction: Stool form is used to inform diagnosis and assess treatment response. The modified Bristol Stool Form Scale for Children (mBSFS-C) classifies stool form into 5 types and is a reliable and valid measure (PMID:21489557). However, a direct comparison of children’s and provider’s ratings using the mBSFS-C vs the Bristol Stool Form Scale (BSFS), which uses 7 stool form types, has not been done. Objectives: To compare the ability of children and providers to characterize stool form using the mBSFS-C vs BSFS and assess scale preference. Methods: Using both scales, children and providers rated the same 35 color stool photos reflecting a wide variety of stool forms. Order of photo presentation and scale use were randomized. After stool ratings, children and providers indicated which scale was easier to use (mBSFS-C vs. BSFS) and which was preferred (mBSFS-C vs. BSFS vs. no preference). For each photo, the modal rating (i.e., most commonly selected rating) was determined for both scales. This was calculated for both the child and provider samples. Then, the percent of child ratings and provider ratings agreeing with their respective modal ratings was determined. Results: Our sample consisted of 200 children (8-18 years, 50% female, mean age 12 ± 3 years) and 35 providers (21 pediatric gastroenterologists, 11 pediatric gastroenterology fellows, and 3 pediatric gastroenterology nurse practitioners). No order effect (mBSFS-C vs BSFS used first) was found. Of the 7,000 child ratings using the mBSFS-C, 84.6% agreed with the children’s modal ratings vs 71.8% using the BSFS. Of the 1225 provider ratings using the mBSFS-C, 90.0% agreed with the provider’s modal ratings vs 77.8% using the BSFS. Considering the providers’ modal ratings as the correct stool form type for each photo, for the mBSFS-C all photograph modal ratings were the same between children and providers (35/35 photos). In contrast, for the BSFS only 86% of the photograph modal ratings (30/35 photos) were the same for both children and providers. Ease of Use: 112 (56%) of children classified the mBSFS-C as the easier scale to use vs. 88 (44%) who identified the BSFS as easier vs 29 (82.8%) and 5 (17.2%) of providers for the mBSFS-C and BSFS, respectively. Scale Preference: 90 (45%) of children preferred the mBSFS-C scale, 68 (34%) preferred the BSFS, and 42 (21%) had no preference. Of providers, 27 (84.4%) preferred the mBSFS-C and 5 (15.6%) preferred the BSFS. Conclusions: 1) The mBSFS-C (vs. BSFS) had greater modal agreement among both children and providers; 2) There was greater concordance in ratings between children and providers with the mBSFS-C vs. BSFS; 3) Children and providers preferred the mBSFS-C and found it easier to use (vs. BSFS). Further studies among different geographic regions/populations are needed to validate these findings.

Amber Cunha

Appearances