Investigation of colorectal disorders; constipation; diarrhoea; lower gastrointestinal haemorrhage; irritable bowel syndrome; haemorrhoids; anal fissures and fistulas; pilonidal sinus; pruritis ani; rectal prolapse; faecal incontinence; appendicitis; diverticular disease; inflammatory bowel disease; colorectal neoplasia - benign colonic tumors; colorectal neoplasia - large bowel cancer; colorectal neoplasia - treatment and prevention; anal cancer; intestinal stomas; large bowel volvulus; colorectal trauma; sexually transmitted diseases and anal papillomas; tropical colonic diseases; paediatric problems; colorectal disorders in elderly people; drugs in the management of colorectal diseases.