Practice parameters and strength of recommendation data: a variable compass.

ABSTRACT

BACKGROUND: Practice parameters and guidelines shape and influence the method and manner in which medicine is practiced. With more than 121 scales and methods of assessing and rating evidence, a comparison of practice parameters can appear daunting. An evaluation of the evidence engenders a sense of the evolution of a specialty and a roadmap for the future. OBJECTIVE: To assess the level of evidence underlying recommendations in allergy-immunology (AI) practice parameters. METHODS: We analyzed the practice parameters that guide AI (n = 15), otolaryngology (n = 8), pediatrics (n = 13), and internal medicine (n = 10) as they appeared on August 30, 2012. Strength of recommendation data was compared after making adjustments for differences in rating scales. RESULTS: The strength of recommendation calculated from strong to weak for the AI practice parameters using a standardized format yielded the following grades A in 195 (13.9%), B in 342 (24.4%), C in 606 (43.2%), D in 231 (16.4%), and E in 29 (2.1%). Controlled trial-based evidence (A and B) demonstrated considerable variability among individual AI practice parameters (range, 1.3%-100%). Evidence from controlled trials was lower in the subspecialty fields (38.3% in AI and 38.2% in otolaryngology) compared with the primary care fields (55.6% in pediatrics and 86.1% in internal medicine). CONCLUSION: Considerable variability exists in the strength of recommendations within the AI practice parameters. The guidelines created by the primary care fields rest on a larger base of evidence collected from controlled trials. These findings likely reflect the adopted approach of making recommendations for less well-studied conditions and practices in AI to assist practitioners and patients and at the same time highlight the myriad opportunities for future research.