Ten-year trends in Canada for selected operations.

Of 16 operations common in Canada the national rates over a 10-year period for the 9 discretionary procedures varied much more than those for the nondiscretionary operations. The rates of tonsillectomy and adenoidectomy, hemorrhoidectomy, varicose vein stripping and appendectomy decreased substantially, whereas those of extraction of lens, cesarean section and colectomy increased. The rates of hysterectomy and cholecystectomy first increased and then decreased. With the exception of Newfoundland the provinces generally followed these trends. Neither the Canadian nor the provincial rates were significantly associated with the availability of hospital beds or surgeons. Factors other than resources probably accounted for much of the variation among the provinces.