lthough the incidence of cervical cancer has declined dramatically since the 1950s, women continue to die from this preventable disease.1 Cervical cytology (Pap smear) screening is well recognized as the major factor con- tributing to the decline in the incidence of cervical cancer. In the past, cervical cancer screening in Ontario was deliv- ered largely in an opportunistic model. The establishment of the Ontario Cervical Cancer Screening Program prompted reorganization of cervical screening delivery in Ontario to improve the clinical effectiveness of cervical screening efforts. A
At the same time, increased understanding of the biology of cervical cancer, especially its relationship to the human papillomavirus (HPV), has led to research focused on cervi- cal cancer prevention. Technological advances have pro- vided new techniques for collecting cervical cells that improve the detection of cervical precursor lesions and that facilitate HPV testing. Because these technologies are evolving rapidly and available systems are expensive, a review of their clinical utility and cost is needed
The volume of published data on cervical screening is extensive. However, within that body of evidence there is a lack of large well-designed studies from which to draw reli- able conclusions, and expert consensus opinion is often used to inform the basis of current practice. A process developed by the Program in Evidence-Based Care2 pro- vides a method for determining the best way to conduct cervical screening, using systematic literature review, vali- dated guideline evaluation instruments, expert consensus, standardized evidence rating systems, internal review and data audit, external validation through a peer-review survey, and final approval by a practice guidelines coordinating committee.
The methodological rigour used in developing the system- atic review and subsequent guidelines is necessary to the production of high-quality products in the face of variable and voluminous evidence. Also important is the involve- ment of key stakeholders, which adds to the credibility and transparency of the process and provides opportunity for feedback. The resulting documents have greater credibility, and the practice guidelines, which by nature are prescrip- tive, are more readily accepted. The participation of key stakeholders also allows peer-to-peer knowledge transfer, which happened throughout Ontario with the cervical can- cer screening guidelines.
The process of developing clinical practice guidelines for Ontario practitioners on cervical screening and the primary management of abnormal cytology using an established methodological process is described.
Ontario Cervical Cancer Screening Clinical Practice Guidelines
A systematic review of the literature and subsequent devel- opment of a clinical practice guideline on cervical screening was initiated by the Ontario Cervical Screening Program in conjunction with the Program in Evidence-Based Care’s Gynecology Cancer Disease Site Group, both programs of Cancer Care Ontario. The project brought together a group of stakeholders, including gynaecologists, family physicians, pathologists, oncologists, and methodologists.
A working group from this committee was struck to lead the process of document development. Administrative sup- port was provided by the Ontario Medical Association Quality Management Program–Laboratory Services. The objectives of the project were to develop evidence-based guidelines, appropriate for use in the Ontario health care setting, on cervical screening and the preliminary management of abnormal cytology.
Literature Search Strategy
The Medline (1998 to July 2004), Embase (1998 to July 2004), and Cochrane Library (2004, Issue 2) databases were searched for relevant practice guidelines, technology assess- ments, systematic reviews, and randomized controlled tri- als. Reference lists of relevant papers and review articles were scanned for additional citations. The Canadian Medical Association Infobase, the National Guidelines Clearinghouse, and other websites were also searched for evidence-based practice guidelines.
From articles identified by the text words and medical sub- ject headings “cervix,” “cervical,” “cancer,” “carcinoma,” “screening,” and “mass screening,” we further identified those with the following study designs: practice guidelines, technology assessments, systematic reviews with or without meta-analyses, and randomized controlled trials.
Study Selection Criteria
The project was framed in terms of six questions (Table 1). The first five questions dealt with the provision of cervical screening, including screening tools, program delivery, initi- ation and cessation of screening, and screening interval. The last question dealt with the primary management of abnormal cervical cytology, not including colposcopic man- agement. Studies addressing quality or the optimization of cervical screening and the management of abnormal cervi- cal cytology were considered eligible in the systematic review of the evidence. The inclusion criteria and outcome variables for each question addressed in the systematic review of the evidence are shown in Table 1. Abstracts, let- ters, and editorials were excluded, as were papers published in a language other than English. Published clinical practice guidelines, technology assessments, systematic reviews, and
APRIL JOGC AVRIL 2007