Nils Fleten

Validation of sick leave measures: self-reported sick leave and sickness benefit data from a Danish national register compared to multiple workplace-registered sick leave spells in a Danish municipality

BackgroundPrevious validation studies of sick leave measures have focused on self-reports. Register-based sick leave data are considered to be valid; however methodological problems may be associated with such data. A Danish national register on sickness benefit (DREAM) has been widely used in sick leave research. On the basis of sick leave records from 3,554 and 2,311 eldercare workers in 14 different workplaces, the aim of this study was to: 1) validate registered sickness benefit data from DREAM against workplace-registered sick leave spells of at least 15 days; 2) validate self-reported sick leave days during one year against workplace-registered sick leave.MethodsAgreement between workplace-registered sick leave and DREAM-registered sickness benefit was reported as sensitivities, specificities and positive predictive values. A receiver-operating characteristic curve and a Bland-Altman plot were used to study the concordance with sick leave duration of the first spell. By means of an analysis of agreement between self-reported and workplace-registered sick leave sensitivity and specificity was calculated. Ninety-five percent confidence intervals (95% CI) were used.ResultsThe probability that registered DREAM data on sickness benefit agrees with workplace-registered sick leave of at least 15 days was 96.7% (95% CI: 95.6-97.6). Specificity was close to 100% (95% CI: 98.3-100). The registered DREAM data on sickness benefit overestimated the duration of sick leave spells by an average of 1.4 (SD: 3.9) weeks. Separate analysis on pregnancy-related sick leave revealed a maximum sensitivity of 20% (95% CI: 4.3-48.1).The sensitivity of self-reporting at least one or at least 56 sick leave day/s was 94.5 (95% CI: 93.4 – 95.5) % and 58.5 (95% CI: 51.1 – 65.6) % respectively. The corresponding specificities were 85.3 (95% CI: 81.4 – 88.6) % and 98.9 (95% CI: 98.3 – 99.3) %.ConclusionsThe DREAM register offered valid measures of sick leave spells of at least 15 days among eldercare employees. Pregnancy-related sick leave should be excluded in studies planning to use DREAM data on sickness benefit. Self-reported sick leave became more imprecise when number of absence days increased, but the sensitivity and specificity were acceptable for lengths not exceeding one week.

Reducing sick leave by minimal postal intervention: a randomised, controlled intervention study

Background: The lack of efficient medical interventions for combating increasing sickness absence rates has lead to the introduction of alternative measures initiated by the Norwegian National Insurance Service or at workplaces. Aim: To determine whether minimal postal intervention had any effect on the length of sick leave. Methods: Randomised, controlled trial with a one year follow up in Northern Norway in 1997 and 1998; 990 consecutive newly sick-listed persons with musculoskeletal or mental disorders were studied. Within the intervention group, 495 eligible sick-listed persons received a general information letter and a questionnaire as their sick leave passed 14 days. Possible intervention effects were analysed by survival analysis of the probability of returning to work within one year, and logistic regressions with benefits at one year as the dependent variable. Results: The overall reduction of 8.3 (95% CI −22.5 to 6.0) calendar days in mean length of sick leaves in the intervention group compared to controls, was not statistically significant. However, intervention significantly reduced length of sick leaves in subgroups with mental disorders, and with rheumatic disorders and arthritis, and overall for sick leaves lasting 12 weeks or more. Young people with low back pain showed an adverse effect to intervention. The overall relative risk of receiving benefits due to sickness after one year in the intervention group was 0.69 (95% CI 0.51 to 0.93) compared to controls. Conclusion: The results should encourage employers, insurance institutions, and authorities to initiate challenges as questions on the length of sick leave and possible modified work measures, during the first few weeks of sick leave, for at least some groups of sick-listed persons.

Length of sick leave – Why not ask the sick-listed? Sick-listed individuals predict their length of sick leave more accurately than professionals

BackgroundThe knowledge of factors accurately predicting the long lasting sick leaves is sparse, but information on medical condition is believed to be necessary to identify persons at risk. Based on the current practice, with identifying sick-listed individuals at risk of long-lasting sick leaves, the objectives of this study were to inquire the diagnostic accuracy of length of sick leaves predicted in the Norwegian National Insurance Offices, and to compare their predictions with the self-predictions of the sick-listed.MethodsBased on medical certificates, two National Insurance medical consultants and two National Insurance officers predicted, at day 14, the length of sick leave in 993 consecutive cases of sick leave, resulting from musculoskeletal or mental disorders, in this 1-year follow-up study. Two months later they reassessed 322 cases based on extended medical certificates. Self-predictions were obtained in 152 sick-listed subjects when their sick leave passed 14 days. Diagnostic accuracy of the predictions was analysed by ROC area, sensitivity, specificity, likelihood ratio, and positive predictive value was included in the analyses of predictive validity.ResultsThe sick-listed identified sick leave lasting 12 weeks or longer with an ROC area of 80.9% (95% CI 73.7–86.8), while the corresponding estimates for medical consultants and officers had ROC areas of 55.6% (95% CI 45.6–65.6%) and 56.0% (95% CI 46.6–65.4%), respectively. The predictions of sick-listed males were significantly better than those of female subjects, and older subjects predicted somewhat better than younger subjects. Neither formal medical competence, nor additional medical information, noticeably improved the diagnostic accuracy based on medical certificates.ConclusionThis study demonstrates that the accuracy of a prognosis based on medical documentation in sickness absence forms, is lower than that of one based on direct communication with the sick-listed themselves.

High referral rates to secondary care by general practitioners in Norway are associated with GPs’ gender and specialist qualifications in family medicine, a study of 4350 consultations

BackgroundReferral rates of general practitioners (GPs) are an important determinant of secondary care utilization. The variation in these rates across GPs is considerable, and cannot be explained by patient morbidity alone. The main objective of this study was to assess the GPs’ referral rate to secondary care in Norway, any associations between the referral decision and patient, GP, health care characteristics and who initiated the referring issue in the consultation.MethodsThe probabilities of referral to secondary care and/or radiological examination were examined in 100 consecutive consultations of 44 randomly chosen Norwegian GPs. The GPs recorded whether the issue of referral was introduced, who introduced it and if the patient was referred. Multilevel and naive multivariable logistic regression analyses were performed to explore associations between the probability of referral and patient, GP and health care characteristics.ResultsOf the 4350 consultations included, 13.7% (GP range 4.0%-28.0%) of patients were referred to secondary somatic and psychiatric care. Female GPs referred significantly more frequently than male GPs (16.0% versus 12.6%, adjusted odds ratio, AOR, 1.25), specialists in family medicine less frequently than their counterparts (12.5% versus 14.9%, AOR 0.76) and salaried GPs more frequently than private practitioners (16.2% versus 12.1%, AOR 1.36).In 4.2% (GP range 0%-12.9%) of the consultations, patients were referred to radiological examination. Specialists in family medicine, salaried GPs and GPs with a Norwegian medical degree referred significantly more frequently to radiological examination than their counterparts (AOR 1.93, 2.00 and 1.73, respectively).The issue of referral was introduced in 23% of the consultations, and in 70.6% of these cases by the GP. The high referrers introduced the referral issue significantly more frequently and also referred a significantly larger proportion when the issue was introduced.ConclusionsThe main finding of the present study was a high overall referral rate, and a striking range among the GPs. Male GPs and specialists in family medicine referred significantly less frequently to secondary care, but the latter referred more frequently to radiological examination. Our findings indicate that intervention on high referrers is a potential area for quality improvement, and there is a need to explore the referral decision process itself.

Unemployment and disability pension--an 18-year follow-up study of a 40-year-old population in a Norwegian county.

BackgroundThis study explored the association of unemployment and an increased risk of receiving disability pension, and the possibility that this risk is attributed to municipality-specific characteristics.MethodsA cohort of 7,985 40-42 year olds was followed for 18 years in national registers, identifying new episodes of unemployment and cases of disability pension. The association between an unemployment period and disability pension in the subsequent year was estimated using discrete time multilevel logistic regressions and clustering individuals by municipality. The association between unemployment and disability pension was adjusted for age in the follow up-period, sex, baseline health status, health behaviour and education level. A conditional intra-class correlation coefficient (ICC) was estimated as a measure of inter-municipality variance.ResultsIn the follow-up period, 2784 (35%) of the participants were granted disability pension. The crude odds ratio for receiving disability pension after unemployment (adjusted for age in follow-up period and sex only) was 1.42 (95% CI 1.1-1.8). Adjusting for baseline health indicators reduced the odds ratio of unemployment to 1.33 (CI 1.1-1.7). A fully adjusted model, including education level, further reduced the odds ratio of unemployment to 1.25 (CI 1.00-1.6). The ICC of the municipality level was approximately 2%.ConclusionsBecoming unemployed increased the risk of receiving subsequent disability pension. However, adjusting for baseline health status, health behaviour and education attenuated this impact considerably. The multilevel analysis indicated that a minor, yet statistically significant, proportion of the risk of disability pension can be attributed to the municipality of residence.

Examining the variation in GPs’ referral practice: a cross-sectional study of GPs’ reasons for referral

Background There is a large variation in referral rates to secondary care among GPs, which is partly unexplained. Aim To explore associations between reasons for referral to secondary care and patient, GP, and healthcare characteristics. Design and setting A cross-sectional study in Northern Norway. Method Data were derived from 44 (42%) of 104 randomly selected GPs between 2008 and 2010. GPs scored the relevance of nine predefined reasons for 595 referrals from 4350 consecutive consultations on a four-level categorical scale. Associations were examined by multivariable ordered and multivariable multilevel logistic regression analyses. Results Medical necessity was assessed as a relevant reason in 93% of the referrals, 43.7% by patient preference, 27.5% to avoid overlooking anything, and 14.6% to reassure the patient. The higher the referral rates, the more frequently the GPs referred to avoid overlooking anything. Female GPs referred to reassure the patient and due to perceived deficient medical knowledge significantly more often than male GPs. However, perceived easy accessibility of specialists was significantly less frequently given as a reason for referral by female GPs compared with male GPs. When the GPs scored the referrals to be of lesser medical necessity, male GPs referred significantly more frequently than female GPs to reassure the patient due to patient preference and perceived deficient medical knowledge. Conclusion There are striking differences in reasons for referral between Norwegian male and female GPs and between GPs with high and low referral rates, which reflects difficulties in handling professional uncertainty. Referring to reassure the patients, especially when referrals are less medically necessary, may reflect consideration and acquiescence towards the patients.

Sickness absence patterns and trends in the health care sector: 5-year monitoring of female municipal employees in the health and care sectors in Norway and Denmark

BackgroundSickness absence is a growing public health problem in Norway and Denmark, with the highest absence rates being registered in Norway. We compared time trends in sickness absence patterns of municipal employees in the health and care sectors in Norway and Denmark.MethodsData from 2004 to 2008 were extracted from the personnel registers of the municipalities of Kristiansand, Norway, and Aarhus, Denmark, for 3,181 and 8,545 female employees, respectively. Age-specific comparative statistics on sickness absence rates (number of calendar days of sickness absence/possible working days) and number of sick leave episodes were calculated for each year of the study period.ResultsThere was an overall increasing trend in sickness absence rates in Denmark (P = 0.002), where rates were highest in the 20–29- (P = 0.01) and 50–59-year-old age groups (P = 0.03). Sickness absence rates in Norway were stable, except for an increase in the 20–29-year-old age group (P = 0.004). In both Norway and Denmark, the mean number of sick leave episodes increased (P <0.0001 and P <0.0001, respectively) in all age groups except for the 30–39- and 60–67-year-old age groups. The proportion of employees without sickness absence was higher in Norway than in Denmark. Both short-term and long-term absence increased in Denmark (P = 0.003 and P <0.0001, respectively), while in Norway, only short-term absence increased (P = 0.09).ConclusionsWe found an overall increase in sickness absence rates in Denmark, while the largest overall increase in sick leave episodes was found in Norway. In both countries, the largest increases were observed among young employees. The results indicate that the two countries are converging in regard to sickness absence measured as rates and episodes.

Work environment and disability pension – an 18-year follow-up study in a Norwegian working population

Aims: To investigate the associations between work environment indicators and health- related work disability. Methods: A health survey of 5,749 working 40–42-year-old Norwegians from Nordland County were linked to a national register for disability pension during a follow-up of over 18 years. The risk for disability pension following various self-reported physical and psychosocial work environmental exposures (individual and cumulative) were estimated using Cox regression analysis. Results: Both cumulative physical and psychosocial work environmental exposures were associated with an increased risk for disability pension, although this association was attenuated for most variables after adjusting for health and education. An increase in five poor psychosocial work environmental exposures was associated with a 22% increased risk for disability (adjusted hazard ratio, aHR, 1.22, 95% CI 1.04–1.44), whereas a similar increase in five poor physical work environmental exposures was associated with a 29% increased risk (aHR, 1.29, 95% CI 1.16-1.44). There were no indications of statistical interaction between either sex or education and work exposures. Conclusions: People who report a poor work environment are at a higher risk for subsequent work disability. This finding suggests that improving working conditions may be an area of intervention in order to reduce the number of people who leave the labour market with a disability pension.

Rehabilitation time before disability pension

BackgroundThe decision to grant a disability pension is usually the end of a long process of medical examinations, treatment and rehabilitation attempts. This study investigates to what extent the time spent on rehabilitation time prior to disability pension is associated with characteristics of the individual or the local employment and welfare office, measured as municipality variance.MethodsA study of 2,533 40 to 42 year olds who received disability pension over a period of 18 years. The logarithm of the rehabilitation time before granting a disability pension was analysed with multilevel regression.ResultsThe rehabilitation time before a disability pension was granted ranged from 30 to 5,508 days. Baseline health characteristics were only moderately associated with rehabilitation time. Younger people and people with unemployment periods had longer rehabilitation time before a disability pension was granted. There were only minor differences in rehabilitation time between men and women and between different levels of education. Approximately 2% of the total variance in rehabilitation time could be attributed to the municipality of residence.ConclusionsThere is a higher threshold for granting a disability pension to younger persons and those who are expecting periods of unemployment, which is reflected in the extended rehabilitation requirements for these groups. The longer rehabilitation period for persons with psychiatric disorders might reflect a lack of common knowledge on the working capacity of and the fitted rehabilitation programs for people with psychiatric disorders.

Sickness certification for patients with acute cough/LRTI in primary care in Poland and Norway.

Abstract Objective. To compare the frequency and duration of sickness certificates issued by GPs to Polish and Norwegian working adults with acute cough/lower respiratory tract infection (LRTI). Design. Cross-sectional observational study with clinicians from nine primary care centres in Poland and 11 primary care centres in Norway. GPs filled out a case report form for all patients, including information on antibiotic prescribing, sickness certification, and advice to stay off work. Setting. Primary care research networks in Poland and Norway. Subjects. Working adults with a new or worsening cough or clinical presentation suggestive of LRTI. Main outcome measures. Issuing sickness certificates and advising patients to stay off work. Results. GPs recorded similar symptoms and signs in patients in the two countries. Antibiotics were prescribed more often in Polish than in Norwegian patients (70.4% vs. 27.1%, p < 0.0001). About half of the patients received a formal sickness certificate (50.5% in Norway and 52.0% in Poland). The proportion of patients advised to stay off work was significantly higher in the Polish sample compared with the Norwegian sample (75.2% vs. 56.1%, p = 0.002). Norwegian GPs less often issued sick certificates for more than seven days (5.6% vs. 36.9%, p < 0.0001). Conclusion. The overall proportion of sickness certification for acute cough/LRTI was similar in Norwegian and Polish patients. However, in the Polish sample, GPs more often advised patients to take time off work without issuing a sick note. When sickness certificates were issued, duration of longer than seven days was more common in Polish than in Norwegian patients.