HONOLULU – One year after the Centers for Disease Control and Prevention issued new recommendations on vaccinating adolescents against pertussis, 96% of pediatricians but only 75% of family physicians were recommending the vaccine routinely, according to a mail-based survey.
In a multivariate analysis, the only two variables independently associated with recommending Tdap were medical specialty (pediatrics vs. family practice) and whether the physician stocked the combined tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap) in their offices, wrote Dr. Amanda F. Dempsey of the University of Michigan, Ann Arbor, and her colleagues.
In March 2006, the CDC's Advisory Committee on Immunization Practices (ACIP) issued recommendations on replacing the adolescent tetanus and diphtheria toxoids (Td) with Tdap. The committee suggested age 11-12 years as the preferred age for Tdap vaccination, and recommended the catch-up vaccination of adolescents aged 13-18 years.
The study involved a mail-based survey of a national sample of 725 pediatricians and 725 family physicians drawn randomly from the American Medical Association's Physician Masterfile. The survey was conducted between January and March 2007. The response rates were 68% for pediatricians and 53% for family physicians, Dr. Dempsey reported in a poster presentation at the joint meeting of the Pediatric Academic Societies.
Survey results showed that 68% of pediatricians were significantly more likely than were family physicians to have adolescent patient volumes above 25%, although most respondents reported that at least 10% of their patients were adolescents.
On the question of Tdap recommendation patterns for 11- to 12-year-old patients, 96% of pediatricians said that they routinely issued such recommendations, 3% said that they sometimes did, and 1% said that they rarely or never did. In contrast, 75% of family physicians said that they routinely recommended the vaccine for their 11- to 12-year-old patients, 12% said they sometimes did, and 13% said that they rarely or never did. These differences were statistically significant.
The results were similar regarding recommendations for Tdap boosters for 13- to 18-year-old patients without a previous Td booster. Among pediatricians, 96% routinely recommended this booster, 3% sometimes did, and 1% rarely or never did. Among family physicians, 80% routinely recommended the booster, 10% sometimes did, and 10% rarely or never did. Once again, the differences were statistically significant.
A lack of adolescent visits was the most frequently cited barrier to administering the Tdap vaccine, with about 33% of physicians citing this as a major barrier and 38% citing it as a minor barrier.
The majority of physicians surveyed said that they found no barriers with regard to Tdap supply, reimbursement, record keeping, or the problem of other priorities during visits.
“Specialty-based differences in immunization practices suggest an ongoing need for provider education, particularly among [family physicians],” they wrote.
The study was funded by the CDC, and Dr. Dempsey reported that she had no conflicts of interest related to her presentation.