Measuring and valuing productivity costs in economic evaluation studies

1. Measuring and valuing productivity costs in economic evaluation studies Marc Koopmanschap, Erasmus Medical Centre Rotterdam The Netherlands

2. History of productivity costs (I) • 1990’s debate on human capital method versus friction cost method versus US panel Qaly method (JHE 1995/1997, HE 1997) • (nowadays consensus that US panel method is invalid) • Focus in this debate on productivity costs in the longer run • Focus on valuation of productivity costs, not so much on the measurement

3. History of productivity costs (II) • Less debated issue: how to measure productivity costs in a valid way • Underresearched area: productivity costs in the short run • Underresearched area: productivity loss without absence/efficiency losses/presenteeism

4. Consensus on productivity costs? • Productivity costs are still quite controversial in economic evaluation of health care (regarding relevance, measurement and valuation) • Hence recommendations for productivity costs in (pharmaco)economic guidelines are quite diverse among countries • Better guidance needed for researchers and policy makers

5. Productivity costs in EE • Relevant if societal perspective used (e.g. drug reimbursement in Netherlands). • Also relevant from perspective of employer • To be applied in worker settings (evaluation of occupational health interventions) and in patient settings (evaluation of health care programs)

6. Crucial information for estimating PC • 1.General information (health, demography, income) • 2.Profession, working situation, functional limitations • 3.Absence from work • 4.Compensation mechanisms (absence from work) • 5.Productivity costs at work (efficiency loss) • 6.Productivity costs at the organisational level • Relevant information: • 7.Administrative and management costs • 8. Hindrance at paid work, quality of life • 9. Hindrance at unpaid work, substitution

7. General information and working situation • General information: self evident. • Working situation: • experienced functional limitations at work as a consequence of health problems • work-related factors: physical and psychosocial factors at work (“mental capital”) • characteristics of the production system (team work, time sensitivity) • These elements together might determine productivity costs due to absence and presenteeism

8. Absence from work • A retrospective question about absence from work during the last 2-3 months, incorporating several possible absence episodes showed a higher response than a day to day question. • This question delivers enough information for calculating productivity costs.

9. Compensation • Compensation encompasses all actions that intend to limit the loss in production/prod costs due to the sick worker’s absence. For example • Colleagues take over work (during normal hours or during overtime) • Extra employees are hired • Sick employees take over after absence during normal hours or during overtime • (Part of) the lost work is not compensated for • These compensation mechanisms may limit productivity costs of absence from work.

10. Results compensation up till 2006 • Jacob–Tacken et al. 2005 confirmed findings Severens: compensation mechanisms may reduce productivity costs substantially: to 40-50% of the value of production. • The occurrence of specific compensation mechanisms depends on the duration of absence • Type of work seems to be explanatory factor • However: Nicholson claims that a workers absence may sometimes induce more productivity costs (team production -> colleagues less productive)

11. Results efficiency loss (I) • Efficiency losses are often substantial: about two hours per day for low back pain patients • For low back pain: absence from work and efficiency loss are positively related • We compared QQ instrument (Brouwer: Vas for quantity of work and for Quality of work) and HLQ (van Roijen: nr of hours to make up for loss) • Construct validity about the same

12. PRODISQ Module E Productiviteit tijdens werk • E1. Op de schaal hieronder kunt u omcirkelen hoeveel werk u tijdens uw laatste werkdag hebt gedaan in uw normale werktijd ten opzichte van een normale werkdag. Een 0 betekent dat u niets kon doen en een 10 dat u evenveel als normaal kon doen.  Niets 0 1 2 3 4 5 6 7 8 9 10 Evenveel als normaal • E2. Op de schaal hieronder kunt u omcirkelen hoe de kwaliteit was van het werk dat u tijdens uw laatste werkdag hebt gedaan ten opzichte van normaal. Een 0 betekent dat uw werk van zeer slechte kwaliteit was en een 10 dat u dezelfde kwaliteit heeft geleverd als normaal. Niets 0 1 2 3 4 5 6 7 8 9 10 Evenveel als normaal

13. Results efficiency loss (II) • QQ produced less missings than HLQ • HLQ often showed no production loss, although patients were hindered in performing work • HLQ may be not applicable for work where making up for lost work is not possible • Overall QQ performed slightly better. • Self reported and actual productivity had a moderate correlation (r=0.48), ceiling effect QQ or limited variance in actual production?

14. Results costs organisation (industrial sector) • Structured interview with managers • Compensation for absence often during normal hours by colleagues • Managers (of 9 industrial companies): more than 70% of efficiency loss is work related • By contrast: workers stated that 64% of productivity costs were related to health problems • Conclusions specific for industrial companies?? • More research needed (in other sectors) !!

15. Results administrative/management costs • Costs of management and administration per case of absence (NL): • On average 90 minutes • 45 minutes in case of short term absence (1 wk) • 2 hours for 1-6 weeks absence • Almost 6 hours for long term absence (> 6 weeks)

16. Results productivity and quality of life • Low back pain (baseline, n=483, EQ5D) • No absence or efficiency loss: avg Qol= 0.7 • Absence: avg Qol 0.65 or lower • Absence 14 days: avg Qol= 0.48 • In case of efficiency loss: • If loss 50-75% of working time: qol = 0.61 • If loss > 75% of working time: qol = 0.51

17. Recommendations for further research • More insight needed in relationship between actual and self reported productivity • Perspective employers vs employees outside industry • Relationship between quantity and quality of production (VAS scales QQ) • Interplay of health, functional limitations, physical/psychological burden, production system on productivity costs • Sample size calculation in interventions: • Often primary outcome health indicator, but… • Absence and presenteeism tend to have skewed distributions with a higher variance, so in general more power needed to demonstrate significant difference in productivity costs between two interventions.

18. PRODISQ references • Website: www.imta.nl (now under reconstruction)Modular instruments and manual, free of charge • Currently busy merging HLQ and PRODISQ • Jacob-Tacken KHM, Koopmanschap MA ea.Correcting for compensating mechanisms related to productivity costs in economic evaluations of health care programs.Health Econ 2005;14:435-43.  • Koopmanschap M, Burdorf A, Jacob K et al. Measuring productivity changes in economic evaluation : setting the research agenda. Pharmacoeconomics. 2005;23(1):47-54 • Lamers LM, et al. The relationship between productivity and health related quality of life: an empirical exploration in persons with low back pain. Quality of life Research 2005; 14: 805-813. • Meerding WJ, IJzelenberg W, Koopmanschap MA et al. Health problems lead to considerable productivity loss among workers with high physical load jobs. Journal of Clinical Epidemiology. 2005; 58:517-23. • Koopmanschap MA. PRODISQ: a modular questionnaire on productivity and disease for economic evaluation studies. Expert Rev Pharmacoeconomics Outcomes Res. 2005;5(1):23-28.