. 2022 Apr 9;35(6):1087–1104. doi: 10.1111/jhn.13005

Table 4.

GRADE Summary of findings on diet therapies

What is the effectiveness of diet therapies on diarrhoea, abdominal pain, and flatulence?
Patients or population: adults with bile acid diarrhoea and chronic diarrhoea
Interventions: Carbohydrate intake modification, fat intake reduction optimised on medication; exclusive elemental (Vivonex)
Setting: Hospital outpatients for carbohydrate intake modification, fat intake reduction; inpatients for exclusive elemental
Outcome	Direction of effect	Number of participants	Certainty of the evidence	Comments
	ROB across studies	(studies)	GRADE
Carbohydrate intake modification on diarrhoea	Positive Serious	2 (1 cohort study)	⊕◯◯◯ Very Low^a ^, ^b ^, ^c	Data in primary BAD only. Long‐term evaluation made (one study, clinician‐reported) but in two patients only. No validated tool used to assess diarrhoea
Fat intake reduction on diarrhoea	Positive Serious	181 (5 cohort studies)	⊕◯◯◯ Very Low^a ^, ^d ^, ^b ^, ^c	Data in secondary BAD, cancer survivors only. Large sample size (one study). Data on sex, age and weight/BMI (two studies). Validated method used to assess diarrhoea (two studies). Longer‐term evaluation made (one study, patient‐reported). Long‐term evaluation made (one study, clinician‐reported)
Exclusive elemental diet therapy on diarrhoea	Positive Serious	9 (2 cohort studies)	⊕◯◯◯ Very Low^a ^, ^b ^, ^c	Data in secondary BAD, Type 1 BAD/BAM only. No validated tool used to assess diarrhoea
Fat intake reduction on abdominal pain	Positive Serious	122 (2 cohort studies)	⊕◯◯◯ Very Low^a ^, ^d ^, ^b	Data in secondary BAD, cancer survivors only. No validated tool used to assess abdominal pain
Fat intake reduction on flatulence	Positive Serious	122 (2 cohort studies)	⊕◯◯◯ Very Low^a ^, ^d ^, ^b	Data in secondary BAD, cancer survivors only. No validated tool used to assess flatulence
Adverse effects	‐ Serious	192 (8 cohort studies)	⊕◯◯◯ Very Low^e	Laxatives: allowed (2 studies), unclear (6 studies). Anti‐diarrhoeals: allowed (3 studies), unclear (5 studies)

Abbreviations: BAD, bile acid diarrhoea; BAM, bile acid malabsorption; BMI, body mass index; GRADE, Grading of Recommendations, Assessment, Development and Evaluation; ROB, risk of bias.

^{^a}

Inconsistency: narrative synthesis conducted, no estimates of the therapy effect possible.

^{^b}

Indirectness: diarrhoea or abdominal pain or flatulence was measured differently across studies, unvalidated tools were used.

^{^c}

Imprecision: population samples were too small to generate precise results.

^{^d}

Inconsistency: differing end‐points across studies to measure therapy effect.

^{^e}

No studies reported on adverse effects.