Rates of adherence to cancer treatment guidelines in Australia and the factors associated with adherence: A systematic review

Adherence to cancer treatment clinical practice guidelines (CPGs) varies enormously across Australia, despite being associated with improved patient outcomes. This systematic review aims to characterize adherence rates to active-cancer treatment CPGs in Australia and related factors to inform future implementation strategies. Five databases were systematically searched, abstracts were screened for eligibility, a full-text review and critical appraisal of eligible studies performed, and data extracted. A narrative synthesis of factors associated with adherence was conducted, and the median adherence rates within cancer streams calculated. A total of 21,031 abstracts were identified. After duplicates were removed, abstracts screened, and full texts reviewed, 20 studies focused on adherence to active-cancer treatment CPGs were included. Overall adherence rates ranged from 29% to 100%. Receipt of guideline recommended treatments was higher for patients who were younger (diffuse large B-cell lymphoma DLBCL], colorectal, lung, and breast cancer); female (breast and lung cancer), and male (DLBCL and colorectal cancer); never smokers (DLBCL and lung cancer); non-Indigenous Australians (cervical and lung cancer); with less advanced stage disease (colorectal, lung, and cervical cancer), without comorbidities (DLBCL, colorectal, and lung cancer); with good-excellent Eastern Cooperative Oncology Group performance status (lung cancer); living in moderately accessible places (colon cancer); and; treated in metropolitan facilities (DLBLC, breast and colon cancer). This review characterized active-cancer treatment CPG adherence rates and associated factors in Australia. Future targeted CPG implementation strategies should account for these factors, to redress unwarranted variation particularly in vulnerable populations, and improve patient outcomes (Prospero number: CRD42020222962).