Rectal examination in patients with pain in the right lower quadrant of the abdomen OBJECTIVE--To determine whether rectal examination provides any diagnostic information in patients admitted to hospital with pain in the right lower quadrant of the abdomen. DESIGN--Casualty officer or surgical registrar recorded symptoms and signs on admission on detailed forms. Final diagnosis was noted on discharge from hospital. SETTING--District general hospital. PATIENTS--1204 Consecutive patients admitted to hospital with pain in the right lower quadrant of the abdomen as their major complaint; 1028 had a rectal examination on admission. MAIN OUTCOME MEASURES--Odds ratio for each symptom and sign related to final diagnosis. Results of multiple logistic regression analysis for acute appendicitis. RESULTS--Right sided rectal tenderness, present in 309 of those examined, was more common in patients with acute appendicitis (odds ratio 1.34, p less than 0.05). This odds ratio was considerably less than that for other clinical signs--namely, tenderness in the right lower quadrant (odds ratio 5.09), rebound tenderness (3.34), guarding (3.07), and muscular rigidity in the abdomen (5.03). In the logistic regression analysis of patients with acute appendicitis, when allowance was made for the presence or absence of rebound tenderness, rectal tenderness on the right lost its significance. Six patients had masses palpable rectally, of which three were palpable on abdominal examination; the other three patients had acute appendicitis. No other unexpected diagnoses were established, and no useful additional diagnostic information was obtained by routine rectal examination. CONCLUSION--If patients presenting with pain in the right lower quadrant of the abdomen are tested for rebound tenderness then rectal examination does not give any further diagnostic information. 