Investigations	Potential results	Clinical management plan: abnormal results
1st Line
Dietary assessment	Excess/deficient fibre intake/resistant starch Inadequate fluids	Referral to dietitian and ask patient to complete 7 day dietary diary in advance. Dietitian to assess food diary to determine dietary fibre intake. Give appropriate advice.
2nd Line
Abdominal X-ray	Constipation	See ‘constipation’ (page 6).
Abdominal X-ray	Faecal loading	Full bowel clearance, eg, Picolax, Klean-Prep, Moviprep. Maintenance bulk laxative. Correct positioning on lavatory and pelvic floor exercises (page 18).
OGD and D2 aspirate and/or glucose hydrogen (methane) breath test	SIBO	Treatment for SIBO (page 17).
Flexible sigmoidoscopy	Newly diagnosed neoplasm	Refer urgently to the appropriate oncology team, requesting an appointment within 2 weeks.
Flexible sigmoidoscopy	Newly diagnosed IBD	Send stool culture. If mild or moderate, refer within 2 weeks to a gastroenterologist. If severe, *this is an emergency*—discuss immediately with a gastroenterologist.
Rectal examination	Pelvic floor dysfunction (page 17) Lax sphincter muscle	Pelvic floor and toileting exercises (page 18). Stool bulking ± antidiarrhoeal agent. Antidiarrhoeal agent ± stimulant laxative suppositories/enemas. Referral for biofeedback (page 18).

IBD, inflammatory bowel disease; OGD, oesophago-gastroduodenoscopy; SIBO, small intestinal bacterial overgrowth.