Development and description of the General Practice Clinical Care Interview
Using Australian published evidence-based clinical guidelines containing quality indicators for Type II diabetes, asthma and ischaemic heart disease/hypertension [15–18], we developed the Australian General Practice Clinical Care Interview (GPCCI), a structured interview instrument to assess the provider-reported care delivered by general practitioners to patients with Type II diabetes, moderate to severe asthma and/or ischaemic heart disease/hypertension. A detailed mapping of the guidelines against the GPCCI is in Appendix I [see Additional file 1]. Experts who were involved in drafting or reviewing the guidelines reviewed and commented on the GPCCI items. The GPCCI was then piloted with 5 general practitioners who were asked to comment on the clarity and comprehension of items.
To minimise the opportunity for general practitioners to answer hypothetically (that is, based on their knowledge of what constitutes best practice) and to capture instead what they actually do on a day-to-day basis, we anchored some of our questions to the general practitioners' specific patients (e.g. 3 newly diagnosed patients with hypertension, 3 patients with Type II diabetes who recently had their HbA1C outside the target range of 7%) and we followed up with questions about whether this care was representative of the care they usually provided to such patients, and if not, how it differed. It also enabled us to capture some of the subjective aspects of quality of care, where the general practitioner knows the patient's personal circumstances and adjusts care accordingly. Other questions asked general practitioners to indicate whether they had performed certain quality functions and to estimate the proportion of their patients who had received different aspects of care.
Four key components of care were assessed for each of the three conditions, as defined by the clinical guidelines:
• case finding, which includes the identification of patients at risk of the condition and methods of screening and diagnosis. Item example: How do you identify patients for assessment of cardiovascular risk factors?
• assessment of the key behavioural and physiological variables and the early detection of complications of the condition. Item example: What proportion of your adult patients with moderate to severe asthma were offered a review of their smoking status in the last 6 months?
• patient education for self management. Item example: Thinking of your newly diagnosed patients with Type 2 diabetes, please jot down the initials or a description of 3 of them. Was self-management education provided to these patients? If yes, who provided it and what did it entail? Was the education provided to these 3 patients typical of what you normally do with newly diagnosed diabetes patients? If not, why not and what is typical?
• ongoing care, which includes how patients who are poorly controlled are managed (including further assessment, changes to treatment and referral), the use of evidenced based guidelines, support for self management, patient-held records, care planning, follow up and monitoring. Item example: How do you follow up people with asthma who do not attend their appointments?
These four components represent key clinical activities of general practice in caring for patients with chronic disease in the Australian health system. The interview schedule consists of 56 questions. Higher clinical scores (max = 78) reflect better clinical care.
Evaluation of the General Practice Clinical Care Interview
We evaluated the psychometric properties of the GPCCI in two ways. First, we conducted an item analysis and tested the internal consistency of the overall scale using Cronbach's alpha. Then we validated our GPCCI against the care recorded in the medical records of the general practitioners' patients with Type 2 diabetes, ischaemic heart disease/hypertension and moderate to severe asthma.
The study was conducted within five Divisions of General Practice in two Australian states, New South Wales and South Australia. The Divisions of General Practice issued invitations to participate in the study to their constituent general practices. Ten general practices agreed to take part, representing a mix of practice types, including solo practitioner (3), group (6) and corporate (1). Six of the practices were in New South Wales, the remaining four were in South Australia.
General practitioners (family physicians) within each of the practices were invited to be interviewed. A minimum sample of 50% of the general practitioners per practice was set in order to ensure representativeness of the data. Eligible patients at the same general practices were invited to participate in the study. Patients were eligible if they had one or more of the target conditions (Type 2 diabetes, moderate to severe asthma and ischaemic heart disease/hypertension, as diagnosed by their general practitioner), aged 18–85 years old, able to read English sufficiently to understand the information and consent forms. Patients were recruited in strict chronological order as they presented at the participating practices for a consultation. The number of patients with each condition reviewed within each practice is in Appendix II [see Additional file 2]. This shows that there was some variability between practices in the number of patients with each condition recruited, however these differences were not statistically significant.
The study was approved by the Human Research Ethics Committees of the University of New South Wales and the University of Adelaide. Participating general practitioners and patients received information on the study and completed a written consent form prior to participation. Practices were compensated for the time of staff participating in the study and patients were entered in a draw for three prizes.
Data collection and analysis
General Practice Clinical Care Interview
The GPCCIs were conducted in the offices of the twenty-eight participating general practitioners. Due to the geographic distance between surgeries, two researchers in each state carried out the interviews, one researcher to one general practitioner interviewee. The researchers were unknown to the general practitioners. Psychometric analyses of the resultant data were conducted, including calculation of the internal consistency of the scale.
Medical record audit
Three data extraction proformas, one each for asthma, Type II diabetes and ischaemic heart disease/hypertension, were developed from the same evidence-based guidelines [15–18] used to develop the GPCCI. The proformas were used to extract information from patients' medical notes and were scored for analysis. Maximum points possible were 14 (diabetes), 11 (asthma) and 9 (heart disease), creating an overall total of 34. Higher scores indicated better clinical care. Five raters extracted the data from the medical records in general practices across the two states, according to a strict protocol. The five raters were post-graduate researchers with experience in conducting research in general practice and clinical experience in chronic disease management.
We verified the reliability of the ratings by analysing the data extracted from 11 patient records (three Type II diabetes, three IHD/hypertension, five asthma) by all five raters. First, single rater reliabilities (or intra-class correlations) were derived from analysis of variance. Single rater reliability is defined by Marsh & Ball as the correlation between two independent assessments of the same subject. One-way ANOVAs were constructed for individual items for each chronic disease. The results were used to assess the strength of agreement between raters for each item in each scale. Using the Spearman-Brown equation, we then calculated reliabilities for the 5 raters for each item.
We removed items that had the same scores from all raters (reliability cannot be calculated) and then conducted a reliability analysis for the adjusted total scores for each chronic disease.
Analysis of the correlation between GPCCI and medical record audit
A comparison of the data items and coding for the GPCCI and each of the medical record audits (for Asthma, Diabetes and IHD/Hypertension) and their distributional characteristics is in Appendix III [see Additional file 3]. This shows that the proportion of codes for each element was similar between the GPCCI and medical record audit. A series of Pearson Product Moment Correlation analyses were performed to ascertain the concurrent validity of the GPCCI in relation to the medical record audit. First we computed the correlations separately for the three disease groups aggregated to practice level, to ascertain whether the interview rating scale had stronger validity as three separate scales. Then, for comparison, we conducted the correlations on the total GPCCI, combined across the three conditions.
All analyses were carried out using SPSS version 12.0.1 for Windows.