Influence of the 'Directions for use' on positivity rates of the HemoccultII (R) test

Objective A concise, detailed, and complete instruction sheet is indispensa ble for adequate completion by the users of a product. This sheet should be enclosed in the envelope which contains Hemoccult II(R) slides. The author s found that the instructions provided by the French manufacturer were unsa tisfactory. They designed a short and simple notice, adequately detailed to be understandable by all volunteers and to obtain satisfactory stool smear s. Positivity rates of Hemoccult II performed with the manufacturer's notic e were compared to those obtained with Hemoccult II performed with the auth ors' instructions. Methods This study was made during the third screening campaign carried out by the Office Departemental de Lutte contre le Cancer (ODLC), This screeni ng programme only concerned women 59 to 69 years of age. Six thousand three hundred and ninety-two Hemoccult II containing the manufacturer's instruct ions were received at the laboratory during March, April, May, June and Jul y 1996, and 2633 Hemoccult II containing the ODLC instructions during March , April, May, June and July 1997. All Hemoccult II were developed and read by one trained technician in the Biochemistry Laboratory (Grenoble Universi ty Hospital). Results The two populations, studied in 1996 and 1997, were strictly compar able in terms of age and number of previous screenings. Out of 6392 Hemoccu lt II containing the manufacturer's instructions, 157 (2.5%) were found pos itive, as compared to 36 (1.4%) Hemoccult II out of 2633 which contained th e authors' instructions. This difference is highly significant (P = 0.001). Conclusion The directions for use provided with Hemoccult II had a crucial influence on positivity rates, and therefore on the cost of screening. The instruction sheet provided by the French manufacturer is not satisfactory a s it contains too much needless information, while several important pieces of advice are missing. Eur J Gastroenterol Hepatol 10:1021-1024 (C) 1998 L ippincott Williams & Wilkins.