Because of substantial sample attrition with so many covariates, and because only 2 variables were consistently associated with the outcome measures, each subsequent multivariable analysis was conducted with each of the primary independent variables and the 2 covariates (patients’ main presenting problem and marital status).
Of the 102 randomly selected family physicians, 83 were eligible because they were still practicing in the area and had adequate office space to accommodate the research assistant. Of these, 39 (47%) agreed to participate and completed the data collection. The participants were similar to the refusers [Table 1] in year of graduation, practice location (rural or urban; high or low socioeconomic status) and sex; however, participants were significantly more likely to be certificants of the College of Family Physicians of Canada than refusers (59% and 27%, respectively; P=.007).
Of 464 eligible patients, 334 (72%) agreed to participate. Nineteen (~6%) were lost to the study. The final 315 participants represented an overall participation rate of 68%; their age was representative of the eligible patients, but there was a higher proportion of men than in the total group of eligible patients.
[Table 2] shows that the slim majority of final participants were women, and most were middle aged and married. Typical of the city, approximately 4 in 10 had more than a high school education. The most common presenting problems were respiratory in nature.
[Table 3] shows the descriptive results for key variables.
Hypothesis Testing Results
The patient-centered communication scores (based on the audiotape analysis) were not significantly related to any of the health outcomes after adjusting for the clustering of patients within practices and after controlling for the 2 confounding variables. Similarly, patient-centered communication scores were not related to any of the 3 medical care outcomes.
Patient-centered communication scores (based on the audiotape analysis) were significantly correlated in the expected direction, with patient perceptions that the patient and physician found common ground (r =-0.16; P=.01). High scores (indicating very patient-centered communication) were correlated with low patient perception scores (indicating patient-centeredness). The 2 other patient perception scores (total patient perception score and the subscore on patient perception that the illness experience was explored) were not significantly associated with patient-centered communication scores.
The total score of patients’ perceptions that the visit was patient centered was associated with positive health outcomes after adjusting for the clustering of patients within practices and after controlling for the 2 confounding variables [Table 4]. Patients’ postencounter levels of discomfort were lower when they perceived the visit to have been patient centered than not.
A similar result occurred for 2 other patient health outcomes: the patients’ postencounter level of concern (P=.02), and the mental health dimension of the SF-36 measure assessed 2 months after the study visit (P=.05). The subscore of patient perceptions that the patient and physician found common ground was associated with one of the health outcomes, the patients’ postencounter level of concern (P=.04). There were no significant associations of the subscore on patients’ perceptions that the illness experience had been explored with any of the patient health outcome measures.
Patients who perceived that their visit had been patient centered received fewer diagnostic tests [Table 5] and referrals [Table 6] in the subsequent 2 months. The proportion receiving diagnostic tests rose from 14.6% in the group who perceived that the visit had been patient centered (total score), to 24.3% in the group who perceived the visit was not. The proportion who were referred doubled from approximately 8% to 16%. These relationships were found even more strongly for the subscore on patient perceptions that the patient and the physician found common ground, but were not found for the subscore on patient perceptions that their illness experience had been explored. The proportion receiving diagnostic tests quadrupled from 4.1% in the group who perceived that the patient and the physician found common ground, to 25.4% in the group who perceived that common ground had not been attained. The proportion who were referred doubled from 6.1% to 14.9%. The number of visits by the patient to the family physician during the subsequent 2 months was not significantly related to the patient perceptions of patient centeredness, although there was a trend (P=.11) with the average number of visits in 2 months in the 4 quartiles of patient perceptions as follows: 1.0, 0.8, 1.2, and 1.3.
Pathway to Improved Patient Outcomes
Patient-centered practice was associated with improved patients’ health status and increased efficiency of care (reduced diagnostic tests and referrals). However, only 1 of the 2 measures of patient-centered practice showed this result, the measure of patients’ perceptions of the patient centeredness of the visit. The measure that was based on ratings of audiotaped physician-patient interactions, while related to the patients’ perception, was not directly related to health status or efficiency.