Crook J. Moldofsky H.

The probability of recovery and return to work from work disability as a function of time.

Quality of Life Research. 3 Suppl 1:S97-109, 1994 Dec.

            This paper describes a prospective longitudinal cohort study of musculoskeletal soft tissue pain impairment following a work related injury. It focuses on specific, univariate prognostic factors indicated in previous research studies that might affect the likelihood that injured workers will return to work or remain on work disability at any point in time. These factors include gender, age, return to work attempts and site of injury. Life table analysis was used to model the probability of work disability. The results showed that different Disability and return to work patterns emerged for males and females. Males were more likely to return to work; however, females had a higher probability than males of remaining at work once they returned to work. Older workers had the highest probability of being off work any given number of days after injury; were less likely To return to work, and if they did, had a higher probability of becoming disabled again. Efforts to return early to work contributed to a decrease in overall work disability. Workers with low back injuries had a greater likelihood of recurrence compared to injuries at other body sites.


Ferguson SA. Marras WS. Gupta P.

Longitudinal quantitative measures of the natural course of low back pain recovery.

Spine. 25(15):1950-6, 2000 Aug 1.

            STUDY DESIGN: A prospective study was developed to quantify acute low back pain recovery. OBJECTIVE: To compare traditional self-report measures of low back pain recovery with a quantitative measure of recovery. SUMMARY OF BACKGROUND DATA: The magnitude of low back disorders in society continues to be a problem. To prevent secondary injuries, an understanding of recovery must be Gained by comparing the natural course of recovery using several outcome measures. METHODS: For this study, 16 occupational and 16 nonoccupational patients with low back pain were recruited. Recovery was monitored prospectively every 2 weeks for 3 to 6 months, using subjective work status, pain symptoms, activities of daily living, and objective functional performance probability (trunk kinematics). RESULTS: Return to work underestimated the percentage of subjects impaired, as compared with all other outcome measures. Symptoms, activities of daily living, and functional performance probability all showed similar patterns of recovery for 0 to 12 weeks. At 14 weeks, there was a lag in functional performance recovery. Both symptoms and activities of daily living indicated that 80% of the population was recovered, whereas functional performance indicated the figure to be 68%. CONCLUSION: This prospective study demonstrates the natural course of recovery using several outcome measures. The objective kinematic functional performance measure of recovery quantifies a different aspect of impairment not evaluated by traditional subjective measures. Use of several outcome measures may lead to a better understanding of low back pain recovery or residual impairment, which may minimize the risk of recurrent injury.


Infante-Rivard C. Lortie M.

Prognostic factors for return to work after a first compensated episode of back pain.

Occupational & Environmental Medicine. 53(7):488-94, 1996 Jul.

        OBJECTIVES--To determine which factors measured at baseline and during the course of treatment influence time to return to work after a first compensated episode of back pain. METHODS--The design is a treatment inception cohort including 305 compensated workers

out of 402 eligible ones presenting at two rehabilitation centres for conventional treatment. Crude and adjusted rate ratios (RRs) along with 95% confidence intervals 95% CIs) were estimated with the Cox's proportional hazards regression. RESULTS--50% of workers had not returned to work after 112 days of follow up, and 11.3% still had not after 270 days. At the end of the study period (maximum follow up time was 1228 days), 230 workers (75.4%) had returned to work, 6.5% had not, and a similar percentage had retired, gone into vocational training, or returned to school. In the Final model stratified for radiating pain during

treatment, which was an important prognostic variable, workers between 21 to 30 years of age had a greater chance of returning to work (RR (95% CI) 1.43 (1.04 to 1.98)

than those > or = 30. The other factors associated with a greater chance of returning to work were: a diagnosis of sprain or pain upsilon a diagnosis of intervertebral disc disorder (2.20 (1.23-3.91)), < 30 days of waiting between the accident and the beginning of treatment

(1.30 (0.96 to 1.77)), a good flexion at baseline (1.52 1.04 to 2.23)), absence of neurological symptoms during treatment (1.40 (0.98-2.00)), > 24 months of employment in the industry (1.49 (1.10 to 2.03)), working for a public industry upsilon a private one (1.63 1.21 to 2.19)), and the ability to take unscheduled breaks (1.45 (1.06 to 1.97)). CONCLUSIONS--Even with a first episode of back pain, time to return to work is long and the proportion not returning is high. Return to work as expected is influenced by disease and host characteristics but also by social and work factors. Reinstatement programmes should account for all these factors.


Rossvoll I. Benum P. Bredland TR. Solstad K. Arntzen E. Jorgensen S.

Incapacity for work in elective orthopaedic surgery:a study of occurrence and the probability of returning to work after treatment.

Journal of Epidemiology & Community Health.

47(5):388-94, 1993 Oct.

            STUDY OBJECTIVE--The extent to which patients undergoing elective surgery for orthopaedic disorders were incapacitated for work while they were on the waiting list and whether they were able to return to work after surgery were studied. DESIGN--This was a prospective cohort study of patients admitted to hospital For elective orthopaedic surgery. Main outcome measures were occurrence of sickness certification during the waiting time, and whether those incapacitated for work at the time of surgery returned to work during the First year after treatment. Multivariate logistic regression was used to estimate adjusted odds ratios for Factors influencing return to work. SETTING--Orthopaedic department in charge of all elective orthopaedic surgery in a population of 197,354 persons in central Norway. SUBJECTS--All 2803 patients admitted to hospital for chronic orthopaedic disorders in the defined population between 1 September 1988 and 31 August 1990 were included in the study. MAIN RESULTS--Of the 1333 patients who were employed, 42% had been certified sick due to the orthopaedic disorder for some period of the waiting time. Sickness benefits from the national insurance scheme (paid from the 15th day of sickness certification) had been received by 33% and were received by 29% at the time of surgery. Of 380 patients incapacitated for work at the time of surgery, 53% returned to work within the first year after surgery. Using those treated within one month of being placed on the waiting list as the reference group, the adjusted odds ratios for not returning to work during the first year After surgery were 9.2 (p < 0.0001) for those who waited more than a year for surgery, 6.2 (p = 0.002) for those waiting nine to 12 months, and 4.9 (p = 0.02) for those waiting for six to nine months. CONCLUSIONS--A high proportion of these patients were incapacitated for work, 53% of those incapacitated returned to work within the first year after surgery. The probability of returning to work after surgery is strongly influenced by the length of time on the waiting list. Waiting for more than one year, compared with immediate treatment, was associated with an adjusted odds ratio of 9.2 for not returning to work.



Injury. 2004 Sep;35(9):891-5.            Related Articles, Links

    Early management and outcome following soft tissue injuries of the neck-a randomised controlled trial.

    Crawford JR, Khan RJ, Varley GW.

    Department of Trauma and Orthopaedics, Peterborough District Hospital, Thorpe Road, Peterborough PE3 6DA, UK.

    A total of 108 consecutive patients presenting to our hospital following a soft tissue injury of the neck from a road traffic accident were included in a prospective trial. Each patient was randomised to either early mobilisation using an exercise regime or 3 weeks treatment in a soft collar followed by the same exercise regime. Patients were assessed clinically at 3, 12 and 52 week intervals from injury. No differences were found between the two groups for pain, range of movement or activities of daily living at any of the follow up intervals. The collar treatment group took significantly longer to return to work after injury (17 days) compared with the early mobilisation group (34 days), [Formula: see text]. Treatment with a soft collar was found to have no obvious benefit in terms of functional recovery after neck injury and was associated with a prolonged time period off work. This study supports the use of an early mobilisation regime following soft tissue injuries of the neck.


Eur J Pain. 2004 Aug;8(4):359-69.

Returning the chronically unemployed with low back pain to employment.

Watson PJ, Booker CK, Moores L, Main CJ.

    Much of the research into return to work following rehabilitation for low back pain in the literature reflects work done in those employed. Unemployment is a consequence of chronic low back pain which has considerable health and economic consequences for the individual and society. This paper describes an occupationally orientated rehabilitation programme for long-term unemployed people (mean duration of unemployment 38.9 months). The aim of the project was to identify factors which predict return to work and progress towards employment. Eight six subjects underwent a pain management rehabilitation programme incorporating vocational focussing and advice, subjects were followed up at 6 months to determine work status. At follow-up 38.4% of subjects were employed and another 23% were in voluntary work, or education/training. There were no significant differences on presenting characteristics between those who returned to work and those who did not. Subjects were divided into those who made positive progress (work, education/training or voluntary work) and those who did not (remained unemployed, dropped out of the programme or lost to follow up). Those who failed to make positive progress were characterised by longer duration of unemployment and higher scores on somatic anxiety and depression. A predictive model was able to identify 80% of those who failed to make progress but prediction of those achieving a positive outcome was poor (44% correct prediction). The factors predicting return to work in unemployed people with low back pain differs from the employed, the need for employment skills training and a vocational focus to rehabilitation are highlighted.



BMC Musculoskelet Disord. 2004 May 24;5(1):14.

Prediction of chronic disability in work-related musculoskeletal disorders: a prospective, population-based study.

    Turner JA, Franklin G, Fulton-Kehoe D, Egan K, Wickizer TM, Lymp JF, Sheppard L, Kaufman JD..

    BACKGROUND: Disability associated with work-related musculoskeletal disorders is an increasingly serious societal problem. Although most injured workers return quickly to work, a substantial number do not. The costs of chronic disability to the injured worker, his or her family, employers, and society are enormous. A means of accurate early identification of injured workers at risk for chronic disability could enable these individuals to be targeted for early intervention to promote return to work and normal functioning. The purpose of this study is to develop statistical models that accurately predict chronic work disability from data obtained from administrative databases and worker interviews soon after a work injury. Based on these models, we will develop a brief instrument that could be administered in medical or workers' compensation settings to screen injured workers for chronic disability risk. METHODS: This is a population-based, prospective study. The study population consists of workers who file claims for work-related back injuries or carpal tunnel syndrome (CTS) in Washington State. The Washington State Department of Labor and Industries claims database is reviewed weekly to identify workers with new claims for work-related back injuries and CTS, and these workers are telephoned and invited to participate. Workers who enroll complete a computer-assisted telephone interview at baseline and one year later. The baseline interview assesses sociodemographic, employment-related, biomedical/health care, legal, and psychosocial risk factors. The follow-up interview assesses pain, disability, and work status. The primary outcome is duration of work disability over the year after claim submission, as assessed by administrative data. Secondary outcomes include work disability status at one year, as assessed by both self-report and work disability compensation status (administrative records). A sample size of 1,800 workers with back injuries and 1,200 with CTS will provide adequate statistical power (0.96 for low back and 0.85 for CTS) to predict disability with an alpha of.05 (two-sided) and a hazard ratio of 1.2. Proportional hazards regression models will be constructed to determine the best combination of predictors of work disability duration at one year. Regression models will also be developed for the secondary outcomes.


Brain Inj. 2004 Mar;18(3):221-38.

Acute predictors of real-world outcomes following traumatic brain injury: a prospective study.

    Dawson DR, Levine B, Schwartz ML, Stuss DT.

    Kunin-Lunenfeld Applied Research Unit, Baycrest Centre for Geriatric Care, Toronto, Ontario, Canada.

    PRIMARY OBJECTIVE: To determine whether the recovery of acute attention and memory improves the prediction of real-world outcomes over that provided by standard demographic and injury-severity measures. RESEARCH DESIGN: Participants were recruited consecutively at the time of injury and followed prospectively at 1 (time 1, or T1) and 4 years (time 2, or T2). METHODS AND PROCEDURES: Measures of attention and memory and the Galveston Orientation and Amnesia Test (GOAT) were administered to 94 participants daily from the time of injury until the criterion was met. Sixty-three per cent returned at T1 and 53% returned at T2. Outcomes were psychosocial distress, return to work and/or school, and quality of life. MAIN OUTCOMES AND RESULTS: Recovery of attention, memory and orientation did not significantly improve prediction of outcomes at T1, but did so at T2. At T2, recovery of free recall of three words over 24 h was a more sensitive predictor of psychosocial distress and return to productivity than the GOAT. CONCLUSIONS: Free recall of three words may be a useful acute clinical test to enhance prediction of long-term outcomes.



J Occup Environ Med. 2003 Jul;45(7):763-70.

Prediction of prolonged work disability in occupational low-back pain based on nurse case management data.

    Okurowski L, Pransky G, Webster B, Shaw WS, Verma S.

    Harvard School of Public Health, South Walpole, MA, USA.

    This study evaluated whether risk prediction data captured by nurse case managers (NCMs) could predict prolonged disability from occupational low back pain. Cases of uncomplicated occupational low back pain referred to NCMs, with dates of injury between January 1, 1997 and June 30, 1998, were selected (n = 986). Predictive information was obtained from the NCM screening checklist of potential risk factors and other administrative claims data. Data were collected on 23 variables thought to predict work status at 6 months postinjury. In a multivariate logistic regression model, being out of work was significantly associated with older age, language barriers, earlier referral to NCM, and neutral or negative attorney attitude toward return to work. The overall predictive power of the model was low (area under curve = 0.6). Although NCM risk factor data collection is feasible and practical in insurance settings, future studies should explore additional variables and refined data collection methods in order to achieve a more accurate prediction.


J Head Trauma Rehabil. 2003 Mar-Apr;18(2):128-38.

Moderating factors in return to work and job stability after traumatic brain injury.

    Kreutzer JS, Marwitz JH, Walker W, Sander A, Sherer M, Bogner J, Fraser R, Bushnik T.

    The Department of Physical Medicine and Rehabilitation, Virginia Commonwealth University, Box 980542, Richmond, VA 23298-0542, USA.

    OBJECTIVE: To examine job stability moderating variables and develop a postinjury work stability prediction model. DESIGN: Multicenter analysis of individuals with traumatic brain injury (TBI) who returned for follow-up at 1, 2, and 3, or 4 years postinjury, were of working age (between 18 and 62 years of age at injury), and were working preinjury. SETTING: Six National Institute on Disability and Rehabilitation Research TBI Model System centers for coordinated acute and rehabilitation care. PARTICIPANTS: A total of 186 adults with TBI were included in the study. MAIN OUTCOME MEASURES: Job stability was categorized as stably employed (employed at all 3 follow-up intervals); unstably employed (employed at one or two of all three follow-up intervals); and unemployed (unemployed at all three follow-up intervals). RESULTS: After injury, 34% were stably employed, 27% were unstably employed, and 39% were unemployed at all three follow-up intervals. Minority group members, people who did not complete high school, and unmarried people were more likely to be unemployed. Driving independence was highly influential and significantly related to employment stability. A discriminant function analysis, which included age, length of unconsciousness and Disability Rating Scale scores at 1 year postinjury, accurately predicted job stability groupings. CONCLUSION: Data analysis provided evidence that employment stability is predictable with a combination of functional, demographic, and injury severity variables. Identification of people at risk for poor employment outcomes early on can facilitate rehabilitation planning and intervention.


Schmerz. 1997 Feb 25;11(1):30-41.

 [Multidisciplinary treatment program on chronic low back pain, part 4. Prognosis of treatment outcome and final conclusions] [Article in German]

    Pfingsten M, Hildebrandt J, Saur P, Franz C, Seeger D.

    Schwerpunkt Algesiologie, Zentrum Anaesthesiologie, Rettungs- und Intensivmedizin, Georg-August-Universitat Gottingen.

    PROBLEM: Studies using a multimodal approach in order to prognose therapeutic success in patients suffering from back pain were seen to have highly diverse results. However, in spite of various independent health care systems, a common interest prevails in identifying determinants of therapeutic success in order to improve therapy. METHODS: Ninety disabled patients with chronic low back pain were admitted to an 8-week out-patient program of functional restoration and behavioral support. The program consisted of a pre-program (education, stretching and calisthenic exercises 4 h a day, three times a week for 3 weeks) and an intensive treatment period (physical exercises, back school education, cognitive behavioral group therapy, relaxation training, occupational therapy, socioeconomic and vocational counseling) which took place for 5 weeks, 7 h a day as an outpatient program. The program's philosophy encourages active effort on the patients' part in order to improve their functional status within a therapeutic environment. This reinforces behavior conducive to getting well, enhances the patients' sense of self-control over their pain and the resulting disability. The main therapeutic target was to facilitate the patients' return to work. Apart from medical examination and personal interview, the patients' physical impairment, pain descriptions, and psychological distress were also measured. This included variables such as depression, psychovegetative complaints, quality of life and workplace satisfaction, disability, and coping with disease. Measurements were repeated at the end of the 8-week program, and following 6 and 12 month intervals. The reliability of prognostic factors in predicting treatment outcome (return to work, reduction of pain intensity, self-assessment of success by the patients) was tested by analyses of variance and discriminant function analyses. RESULTS: Patients' return to the workplace could be predicted in 85% of cases based on whether an application for pension had been made, on the length of duration of work disability, and on "fixed" assumptions on the part of the patient concerning his work situation. Pre-treatment somatic findings (for example, diagnosis, degree of physical impairment, and functional debilities), together with depressive and psychovegetative reactions, were shown to have no connection with the patient's ability to return to the workplace. Similar findings were demonstrated for the prediction of pain reduction and patient satisfaction with treatment. CONCLUSIONS: Predicting successful treatment is hardly possible without analyzing individual circumstances, focusing on sociodemographic variables, workplace-related conditions, and aspects of individual motivation. With regard to objective therapeutic success, subjective perceptions proved highly influential. Treatment proved successful only when the patient's perception of functional disability was minimized. Hence, individual perceptions and experiences were more important than physical capabilities.


Spine. 2002 Dec 1;27(23):2720-5.

Biopsychosocial multivariate predictive model of occupational low back disability.

    Schultz IZ, Crook JM, Berkowitz J, Meloche GR, Milner R, Zuberbier OA, Meloche W.

    Department of Educational and Counselling Psychology and Special Education, University of British Columbia, Vancouver, Canada.

    STUDY DESIGN: To establish outcome, 253 workers with subacute and chronic low back conditions were assessed with a comprehensive multimethod biopsychosocial protocol at baseline, 3 days after the initial examination, and 3 months later. OBJECTIVE: To validate empirically a biopsychosocial model for prediction of occupational low back disability. SUMMARY OF BACKGROUND DATA: Costs of low back occupational disability continue to spiral despite stabilization of low back injury rates. An empirically based model to predict occupational disability in workers with low back injuries is required. METHODS: Workers with subacute low back injuries (4-6 weeks after injury, n = 192) and those with chronic back pain (6-12 months after injury, n = 61) were the study participants. The biopsychosocial protocol included five groups of variables: 1) sociodemographic, 2) medical, 3) psychosocial, 4) pain behavior, and 5) workplace-related factors. Predictive validity was investigated through a 3-month follow-up assessment, at which time the return to work outcome was determined. Stepwise logistic regression models were developed to predict work status. RESULTS: The final integrated model consisted of variables from a wide biopsychosocial spectrum: vitality, health transition, feeling that job is threatened due to injury, expectations of recovery, guarding behavior, perception of severity of disability, time to complete walk, and right leg typical sciatica. CONCLUSIONS: The "winning" variables identified in the integrated model are dominated by cognitions, which are accompanied by disability behaviors. A cognitive-behavioral model with an adaptation-oriented rather than a pathology-oriented focus is favored for early intervention with high-risk workers since cognitions are amenable to change.


Spine. 2002 Dec 1;27(23):2715-9.

Are components of a comprehensive medical assessment predictive of work disability after an episode of occupational low back trouble?

    Hunt DG, Zuberbier OA, Kozlowski AJ, Berkowitz J, Schultz IZ, Milner RA, Crook JM, Turk DC.

    Workers Compensation Board of British Columbia, Vancouver, British Columbia, Canada.

    STUDY DESIGN: One hundred fifty-nine subacute low back work-injured patients completed a full medical assessment at baseline. A full repeat examination was performed 3 months later, when return-to-work status was determined. OBJECTIVE: To determine the prognostic value of a comprehensive medical assessment for the prediction of return-to-work status. SUMMARY OF BACKGROUND DATA: A systematic review of the work disability prediction literature of low back trouble prognosis revealed that no high-quality studies included a full medical history and physical examination in the design. The results of studies included in the systematic review were equivocal with respect to predictive usefulness of medical variables. METHODS: Participants completed medical history questionnaires and then were clinically examined by one of six experienced examiners (three physicians and three physiotherapists). Return-to-work status was measured 3 months later, and predictive validity was evaluated using logistic regression modeling. RESULTS: Medical variables (, medical history subscales, physical examination subscales, and lumbar range-of-motion tests) showed modest correct classification rates varying between 61.6% and 69.1% for participants. CONCLUSIONS: Comprehensive medical assessments play a crucial role in the early identification of serious pathology after low back trouble. We were unable to identify, however, any medical evaluation variables that would account for significant proportions of variance in return to work. The weight of evidence obtained in this study suggests that injured workers' subjective interpretations and appraisals may be more powerful predictors of the course of postinjury recovery than exclusively medical assessments.


Work. 1999;12(1):25-35.

The model of human occupation and prediction of return to work: a review of related empirical research.

    Braveman B.

    Department of Occupational Therapy, University of Illinois at Chicago, USA.

    The purpose of this paper is to investigate through a review of research literature whether empirical support exists to support the theoretical arguments of the Model of Human Occupation. A literature review of 44 predictive studies of factors influencing return-to-work published over the last 25 years was conducted. The factors most commonly found to be associated with return to work or with long-term disability were then organized according to the subsystems of the Model of Human Occupation.


Eur Spine J. 2002 Jun;11(3):258-66. Epub 2001 Oct 05.

Predictive tests for non-return to work in patients with chronic low back pain.

    Kool JP, Oesch PR, de Bie RA.

    Research Department, Rehabilitation Centre, Klinik Valens, 7317 Valens, Switzerland.

    Return to work (RTW) is the primary goal in the rehabilitation of patients with chronic low back pain. In spite of expensive rehabilitative efforts, many patients do not RTW. To increase cost effectiveness, predictive tests for non-RTW are needed to select patients for rehabilitation. The reliability of these tests must be high, to prevent exclusion of patients who might improve. This study evaluates the reliability and predictive validity of four tests and the following psychosocial factors for non-RTW: nationality, off-work duration, unemployment and work load. It was designed as a prospective cohort study of 99 patients with chronic low back pain. Upon entry, physical work load, time off work, unemployment and nationality were recorded. The study investigated four tests with an anticipated prognostic value for non-RTW: the Numeric Pain Rating Scale (NRS, 9-10 of a maximum of 10), the Step Test and Pseudo Strength Test (precipitous cessation) and Behavioural Signs. After 12 months, the RTW rate was obtained from the physicians responsible for sick-listing by postal survey. The response rate regarding RTW was 91% at 1 year. The RTW rate at 1 year was 20%. All investigated tests significantly correlated with non-RTW. Regression analysis showed that the best prediction of non-RTW was obtained when at least two out of the four tests were positive (positive predictive value 0.97, sensitivity 0.45). Unemployment, time off work, nationality and physical work load were less predictive. The results show that the combination of the four prognostic tests allows a very reliable prognosis of non-RTW. The cost effectiveness of rehabilitation aiming at RTW will, therefore, be increased by excluding patients with two or more positive tests.