To determine the effect of advice given in routine primary care consultations on levels of physical activity.

MEDLINE (from 1966 to December 2000), EMBASE (from 1980 to December 2000), SPORTDiscus (from 1975 to December 2000), the Cochrane Database of Systematic Reviews and the Cochrane Controlled Trials Register were searched. The search terms were listed in the paper. The bibliographies of retrieved papers were examined for further references and experts in the field were contacted. Attempts to contact all authors of included studies, to identify additional published or unpublished studies, were also made. No language restrictions were imposed.

Study designs of evaluations included in the review

The included studies had to have a control group who had not received advice to increase their activity levels. The review therefore included both randomised controlled trials (RCTs) and studies of a non-randomised design.

Specific interventions included in the review

The studies had to include an assessment of the effectiveness of advice (defined as verbal, written or other forms of advice) given within the confines of a routine consultation in a primary care setting, with the aim of increasing levels of physical activity. Advice could be provided by any primary health care professional. Studies that offered activity advice as part of a package of lifestyle advice were also included.

The specific interventions all included verbal advice; some also included an assessment of the patients' stage of change, or the provision of written or videotaped information in addition to the oral advice.

Participants included in the review

The authors did not state specific inclusion criteria in relation to the participants included in the review. The review therefore included sedentary adults aged over 18 years who had no mobility limitations.

Outcomes assessed in the review

All of the included studies had to have an outcome measure of physical activity level. This was assessed through a self-report questionnaire or a telephone interview. However, studies in which the sole outcome measure was motivation to exercise or self efficacy were excluded.

How were decisions on the relevance of primary studies made?

The authors stated that all the abstracts were read, and if there was any doubt about the relevance of a paper then it was retrieved.

Study quality was assessed upon whether the study was a RCT, allocation to the intervention groups was adequately concealed, the analysis was undertaken on an intention-to-treat basis, the outcome assessment was blinded, and the activity levels were objectively validated. Two reviewers independently assessed validity and resolved any discrepancies by discussion. A third party was available if agreement could not be reached.

Two reviewers independently extracted the data using a structured form. Data on the type of study design, number of participants, interventions, results, authors' conclusion and quality were extracted and tabulated.

How were the studies combined?

A narrative synthesis of the studies was undertaken.

How were differences between studies investigated?

Differences between the studies were explored according to study quality. The factors of participant randomisation, allocation concealment, blinded outcome assessment, use of intention-to-treat analysis and the use of objectively validated exercise measures were used to explore differences between the results of the studies.

Nine studies were included, with data from eight being presented (5,102 participants): 2 RCTs (1,113 participants) and 6 controlled clinical trials (3,989 participants).

Four of the 6 studies that reported short-term results (up to 8 weeks) found the advice to be effective at increasing activity. Only one of the 4 studies reporting long-term results (4 months or more) showed the advice to be effective at increasing physical activity in the long term. One of the RCTs found null results at both the short-term and long-term follow-up; the other only assessed the outcome beyond 4 months and found null effects at both 4 and 12 months.

From the available evidence it appears that advice in routine primary care consultations is not an effective means of producing sustained increases in physical activity. However, as six of the included studies were conducted in the USA and the other two in Australia, these results may not be applicable to the United Kingdom, where the structure of primary care is unique.

This was a reasonably well-conducted review. The authors addressed a clear review question in relation to the type of interventions and the outcome measures that were to be assessed. However, a lack of an a priori-specified patient population may affect the generalisability of the review's findings. The literature search was thorough and no language restrictions were imposed. However, unpublished studies were not searched for, and it is therefore possible that unpublished data may have been missed. Two reviewers independently undertook a systematic validity assessment and the data were extracted independently. Any biases in the systematic review process are therefore likely to have been minimised and any errors in the data extraction detected. The authors provided adequate information on the primary included studies to allow the reader to fully interpret the results and conclusions. The use of a narrative synthesis was appropriate, with the differences between the findings of the studies being adequately explored. Overall, it appears that the authors' conclusions follow from the evidence base reviewed.

Practice: The authors did not state any implications for practice.

Research: The authors stated that one of the most important findings was that no studies in the United Kingdom have evaluated the effect of advice within routine primary care consultations to promote physical activity. Quality research within UK primary care would, therefore, be valuable.

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.