Strengths and limitations of the study
Two control groups were used with the same GPs participating in the intervention group and control group 2. This design has two advantages: it enabled estimation of the outcome difference with greater precision, and it increased the efficiency of the study by using fewer GPs. Nevertheless, it can also be considered a potential problem, as GPs could carry the new intervention over to their usual care, leading to contamination bias at the GP level. In this case the direction of bias would go against the hypothesis that the 7H+T intervention is effective. Even so, and despite this, significant differences were seen between the intervention group and control group 2. Therefore, it can be argued that this strategy adds strength to the study's conclusions.
These GPs were trained in the 7H+T intervention and were convinced of its worth and efficiency, so they may have found it difficult not to apply it with their other patients, even though they were blinded to these patients, as was the case for control group 2. Therefore, it can be presumed that the 7H+T intervention has now become part of everyday practice for those GPs involved, which supports the hypothesis that the 7H+T intervention is related to important changes in GP practice.
As the frequent-attender groups were similar at baseline, selection bias is unlikely to have influenced the study's findings. Furthermore, the use of multilevel analysis in which adjustment was made for possible effects of clustering and the exhaustive measurement of variables that contribute to explain frequent attendance, provided greater control in the analyses. Five covariates were adjusted for: age, satisfaction with GP, number of chronic diseases, anxiety, and hypochondria. If questionnaires had not been used, anxiety and hypochondria as diagnosed by the GPs would not have been controlled for. These psychosocial variables are important predictors of frequent attendance,39,40 and the capacity to detect them varies widely among GPs.41
The frequent attenders who fulfilled the exclusion criteria during follow-up were younger and healthier than those who did not fulfill them. Most of the families who attended San José Health Centre worked in the local car industry, which at that time was in crisis, thereby explaining why some participants had to leave the area in search of a new job. This could have introduced a selection bias, although an attempt was made to minimize it by including these absent workers in the final analysis, with their outcome variable estimated using multiple imputation methods.
Although there was no significant difference between groups in the number of referrals to specialists during the post-intervention year, no assessment was made of the number of repeat visits to specialists during the follow-up because that information was unavailable; therefore, this might have involved an ‘off utilisation’ bias. Similarly, the 7H+T intervention encouraged the involvement of other members of the health centre team, especially nurses and social workers, although these visits were controlled for in the analyses.
Although the number of patients in the sample was sufficient for the study's objective, only six GPs were included in the study; hence the results have limited external validity. When the study was designed it was decided not to use larger samples because there was previously no evidence of successful comprehensive GP interventions with frequent attenders.
In the opinion of the intervention GPs, frequent attendance was due to many different causes (or hypotheses) in each patient. The column entitled ‘Decision to refute’ in Table 2 shows the difficulty these GPs experienced about feeling sure of the hypothesis in question. They had more problems with the social (82.6%) and psychological hypotheses (67.6%), which agrees with predominant biomedical opinion.42 Difficulty being convinced about the administrative–organisational hypothesis was situated second.
GPs commented that frequent attenders too often attended just to obtain prescriptions. Although this type of visit was apparently administrative, it often included biological or psychosocial components. The biological aspect generally concerned repeat visits for stable chronic patients;43 the psychosocial aspect might be related to a kind of ‘entry ticket’ that masked the true reason for the request for a consultation. Perhaps patients considered that seeking help for psychosocial problems would be less acceptable (both socially and by their GPs) than asking for medical prescriptions. This is very common in Spanish primary care,44 and its modification with the GP intervention may well have contributed greatly to reducing consultations by frequent attenders.
An intervention was developed with frequent attenders and its effectiveness at decreasing their consultations evaluated. However, the active components and mechanisms of this intervention need to be elucidated. Future exploratory studies of this intervention should be undertaken. Independent health variables (self-reported health, disease diagnoses, and psychosocial variables) could have been assessed at baseline and at the end of the follow-up, which would have revealed the relationship between improvement in health and psychosocial variables, and the reduction in consultations.
The GP intervention group reported a qualitative improvement in their doctor–patient relationships, although a second score in the emotional questionnaire34 at the end of the follow-up might have added more discriminatory information. GPs often find themselves in dysfunctional doctor–frequent-attender relationships,11–34 although it remains unclear how this influences frequent attendance.
Perhaps alleviating GPs' anxiety, fears, or uncertainty about dealing with frequent attenders could help to reduce frequent attendance.45 One could therefore suggest that it was not the intervention itself that produced the results but rather the ‘Hawthorne effect’,11 whereby just having the opportunity to have their concerns taken seriously and to share with others their experience of frequent attenders enabled GPs to feel more able to reduce the number of visits by their frequent attenders. The authors also believe that intervening as a team of GPs improved the efficiency of decision making in regards to frequent attenders. Colleagues were able to help with the decisions because they did not know the specific frequent attender and were therefore emotionally more neutral.