Investigating practice variation in a changing primary care. A multilevel perspective on The Skaraborg Primary Care Database

Background and Aims: Differences in the clinical care of patients have been explained through the concept of practice variation, that is, the occurrence of established local medical procedures that varies between geographic areas. The primary measures introduced to eliminate undesirable differences in medical care are the introduction of medical guidelines and economical incentives that rewards the desired behaviour. Practice variation in primary care can be seen on different hierarchically organised levels (e.g. patient, physician, health care center (HCC)) and Multilevel Regression analysis techniques (MLRA) offer a suitable tool to analyse these kinds of data. Data extracted from computerised medical records are ideal for studying practice variation as they often comprise information from several levels. In the region of Skaraborg in Sweden a new database, the Skaraborg Primary care database (SPCD), comprising information extracted form the computerised medical records of all public health care centres has recently been established. The overall aims of this thesis were to examine the usefulness and quality of the SPCD database for research and to study practice variation in some important areas such as diagnosis registration, laboratory analysis ordering and prescriptions. Furthermore, the influence of changes in the economic incentives on physician’s clinical behaviour was investigated. Material and Methods: In all studies data from the SPCD comprising data on individual patients from all public health care centres was used. The registration of diagnoses in the SPCD was validated by comparing the occurrence of recorded diagnosis in the diagnosis register of the database with the free text part of the patient medical records for a randomly selected sample of patients. Multilevel logistic regression analysis was used to investigate practice variation in prescribing and laboratory test ordering, focusing on measures of both frequency and variance. The effects of changes in economic incentives for diagnosis coding and prescribing were examined by comparing multilevel analysis results before and after implementation of the economic incentives. Results and Conclusions: The frequency of registration of ICD codes varied between diagnoses but also between physicians and HCCs. Different diagnoses need to be validated separately. The occurrence of practice variation was demonstrated both in laboratory test ordering where the physician level was the most important level and in prescribing where physician and HCC levels were equally important in explaining the observed variation. A positive effect in adherence to prescribing guidelines was demonstrated after the introduction of a decentralised drug budget. The introduction of a strong economic incentive for ICD coding showed the expected rise in coding rates and decline in variation, directly affecting the diagnoses register of the research database. Changes in the healthcare process will have a direct impact on the research database. Knowledge about the local health care processes is essential when interpreting database data. The SPCD seems as a good complement to previously established databases and quality registers, offering new possibilities when studying primary care

Variation in plasma calcium analysis in primary care in Sweden - a multilevel analysis

<p>Abstract</p> <p>Background</p> <p>Primary hyperparathyroidism (pHPT) is a common disease that often remains undetected and causes severe disturbance especially in postmenopausal women. Therefore, national recommendations promoting early pHPT detection by plasma calcium (P-Ca) have been issued in Sweden. In this study we aimed to investigate variation of P-Ca analysis between physicians and health care centres (HCCs) in primary care in county of Skaraborg, Sweden.</p> <p>Methods</p> <p>In this cross sectional study of patients' records during 2005 we analysed records from 154 629 patients attending 457 physicians at 24 HCCs. We used multilevel logistic regression analysis (MLRA) and adjusted for patient, physician and HCC characteristics. Differences were expressed as median odds ratio (MOR).</p> <p>Results</p> <p>There was a substantial variation in number of P-Ca analyses between both HCCs (MOR_HCC1.65 [1.44-2.07]) and physicians (MOR_physician1.95 [1.85-2.08]). The odds for a P-Ca analysis were lower for male patients (OR 0.80 [0.77-0.83]) and increased with the number of diagnoses (OR 25.8 [23.5-28.5]). Sex of the physician had no influence on P-Ca test ordering (OR 0.93 [0.78-1.09]). Physicians under education ordered most P-Ca analyses (OR 1.69 [1.35-2.24]) and locum least (OR 0.73 [0.57-0.94]). More of the variance was attributed to the physician level than the HCC level. Different mix of patients did not explain this variance between physicians. Theoretically, if a patient were able to change both GP and HCC, the odds of a P-Ca analysis would in median increase by 2.45. Including characteristics of the patients, physicians and HCCs in the MLRA model did not explain the variance.</p> <p>Conclusions</p> <p>The physician level was more important than the HCC level for the variation in P-Ca analysis, but further exploration of unidentified contextual factors is crucial for future monitoring of practice variation.</p

Validity of registration of ICD codes and prescriptions in a research database in Swedish primary care: a cross-sectional study in Skaraborg primary care database

<p>Abstract</p> <p>Background</p> <p>In recent years, several primary care databases recording information from computerized medical records have been established and used for quality assessment of medical care and research. However, to be useful for research purposes, the data generated routinely from every day practice require registration of high quality. In this study we aimed to investigate (i) the frequency and validity of ICD code and drug prescription registration in the new Skaraborg primary care database (SPCD) and (ii) to investigate the sources of variation in this registration.</p> <p>Methods</p> <p>SPCD contains anonymous electronic medical records (ProfDoc III) automatically retrieved from all 24 public health care centres (HCC) in Skaraborg, Sweden. The frequencies of ICD code registration for the selected diagnoses diabetes mellitus, hypertension and chronic cardiovascular disease and the relevant drug prescriptions in the time period between May 2002 and October 2003 were analysed. The validity of data registration in the SPCD was assessed in a random sample of 50 medical records from each HCC (n = 1200 records) using the medical record text as gold standard. The variance of ICD code registration was studied with multi-level logistic regression analysis and expressed as median odds ratio (MOR).</p> <p>Results</p> <p>For diabetes mellitus and hypertension ICD codes were registered in 80-90% of cases, while for congestive heart failure and ischemic heart disease ICD codes were registered more seldom (60-70%). Drug prescription registration was overall high (88%). A correlation between the frequency of ICD coded visits and the sensitivity of the ICD code registration was found for hypertension and congestive heart failure but not for diabetes or ischemic heart disease.</p> <p>The frequency of ICD code registration varied from 42 to 90% between HCCs, and the greatest variation was found at the physician level (MOR_PHYSICIAN= 4.2 and MOR_HCC= 2.3).</p> <p>Conclusions</p> <p>Since the frequency of ICD code registration varies between different diagnoses, each diagnosis must be separately validated. Improved frequency and quality of ICD code registration might be achieved by interventions directed towards the physicians where the greatest amount of variation was found.</p

Coding of procedures documented by general practitioners in Swedish primary care-an explorative study using two procedure coding systems

<p>Abstract</p> <p>Background</p> <p>Procedures documented by general practitioners in primary care have not been studied in relation to procedure coding systems. We aimed to describe procedures documented by Swedish general practitioners in electronic patient records and to compare them to the Swedish Classification of Health Interventions (KVÅ) and SNOMED CT.</p> <p>Methods</p> <p>Procedures in 200 record entries were identified, coded, assessed in relation to two procedure coding systems and analysed.</p> <p>Results</p> <p>417 procedures found in the 200 electronic patient record entries were coded with 36 different Classification of Health Interventions categories and 148 different SNOMED CT concepts. 22.8% of the procedures could not be coded with any Classification of Health Interventions category and 4.3% could not be coded with any SNOMED CT concept. 206 procedure-concept/category pairs were assessed as a complete match in SNOMED CT compared to 10 in the Classification of Health Interventions.</p> <p>Conclusions</p> <p>Procedures documented by general practitioners were present in nearly all electronic patient record entries. Almost all procedures could be coded using SNOMED CT.</p> <p>Classification of Health Interventions covered the procedures to a lesser extent and with a much lower degree of concordance. SNOMED CT is a more flexible terminology system that can be used for different purposes for procedure coding in primary care.</p

Adaptation of multi-joint movements during postural disturbances.

The objective was to investigate the adaptation ofthe multi-segmented body movements induced over time byvibratory proprioceptive stimulation of the calf muscles and by galvanic vestibular stimulation. Twelve normal subjects were with eyes open or eyes closed exposed to vibratory stimulation of two different amplitudes and frequencies, or to simultaneously applied galvanic and vibratory stimulation. Multi-input multi-output system identification methods as well as quantitative analysis were applied to the biomechanical experimental data of anteroposterior and lateral body movements and torques induced towards the ground. The immediate adaptive response to the stimulation onset was that the subjects adopted a more rigid posture with coordinated movements of primarily head-shoulder and headhip body segments. The body-movement amplitudes at allmeasured sites as well as the amplitudes of the ground support forces decreased over time as a result of another, somewhat slower adaptation process. The subjects required more time to adapt to a rigid movement pattern when the subjects were simultaneously exposed to both galvanic and vibratorystimulation. Moreover, the accuracy of the MIMO model andcorrelation analysis between measured torque variance andhead; shoulder; hip and knee movement variance suggests thatforce platform recordings reflect both in anteroposterior and lateral direction the body movements at these sites

Adaptation of Multi-Segmented Body Movements during Vibratory Proprioceptive and Galvanic Vestibular Stimulation.

Control of orthograde posture and use of adaptive adjustments constitutes essential topics of human movement control, both in maintenance of static posture and in ensuring body stability during locomotion. The objective was to investigate, in twelve normal subjects, how head, shoulder, hip and knee movements and torques induced towards the support surface were affected by vibratory proprioceptive and galvanic vestibular stimulation, and to investigate whether movement pattern, body posture and movement coordination were changed over time. Our findings suggest that the adaptive process to enhance stability involves both alteration of the multi-segmented movement pattern and alteration of body posture. The magnitude of the vibratory stimulation intensity had a prominent influence on the evoked multi-segmented movement pattern. The trial conditions also influenced whether the posture were altered and if these posture adjustments were done directly at stimulation onset or gradually over a longer period. Moreover, the correlation values showed that the subjects, primarily during trials with vibratory stimulation alone, significantly increased the body movement coordination at stimulation onset and maintained this movement pattern throughout the stimulation period. Furthermore, when exposed to balance perturbations the test subjects synchronized significantly the head and torso movements in anteroposterior direction during all trial conditions

Prediction of treatment response in patients with newly diagnosed type 2 diabetes : The Skaraborg diabetes register

Aims: Type 2 diabetes is associated with cardiovascular complications. It is largely unknown which patients have poor treatment response and high complication risk; biomarkers are studied for this purpose. The aim of the study was to investigate the association between clinical factors such as HbA1c, level of biomarkers (C-peptide, copeptin) at diagnosis and changes in HbA1c, blood pressure or body mass index (BMI) after five years. Methods: Clinical data and blood samples from 460 newly diagnosed type 2 diabetes patients from the Skaraborg diabetes register (SDR) at diagnosis and after 5. years and were analyzed with linear and logistic regressions. Results: High BMI at diagnosis and smoking were associated with less reduction of HbA1c i.e. poorer treatment outcome after 5. years. A high HbA1c at baseline predicted a greater reduction of HbA1c and need for insulin treatment. High systolic blood pressure and BMI at baseline were associated with greater reduction.The biomarkers were not associated with increase of blood pressure, HbA1c, BMI or need for insulin treatment. Conclusions: Smokers and patients with high HbA1c at diagnosis respond poorer to treatment over 5. years. This highlights the importance of advice for non-smoking and weight reduction and more intensive treatment over time

Increased registration of hypertension and cancer diagnoses after the introduction of a new reimbursement system

Objective. To investigate the impact on ICD coding behaviour of a new case-mix reimbursement system based on coded patient diagnoses. The main hypothesis was that after the introduction of the new system the coding of chronic diseases like hypertension and cancer would increase and the variance in propensity for coding would decrease on both physician and health care centre (HCC) levels. Design. Cross-sectional multilevel logistic regression analyses were performed in periods covering the time before and after the introduction of the new reimbursement system. Setting. Skaraborg primary care, Sweden. Subjects. All patients (n = 76 546 to 79 826) 50 years of age and older visiting 468 to 627 physicians at the 22 public HCCs in five consecutive time periods of one year each. Main outcome measures. Registered codes for hypertension and cancer diseases in Skaraborg primary care database (SPCD). Results. After the introduction of the new reimbursement system the adjusted prevalence of hypertension and cancer in SPCD increased from 17.4% to 32.2% and from 0.79% to 2.32%, respectively, probably partly due to an increased diagnosis coding of indirect patient contacts. The total variance in the propensity for coding declined simultaneously at the physician level for both diagnosis groups. Conclusions. Changes in the healthcare reimbursement system may directly influence the contents of a research database that retrieves data from clinical practice. This should be taken into account when using such a database for research purposes, and the data should be validated for each diagnosis