Effectiveness of 'motivational interviewing' on sick leave: a randomized controlled trial in a social insurance setting

Abstract

Objective: This study aimed to evaluate the effectiveness of motivational interviewing (MI) - a counselling approach offered by caseworkers at the Norwegian Labor and Welfare Administration (NAV) - on return to work (RTW) for individuals sick-listed for ≥8 weeks due to any diagnoses. MI was compared to usual case management and an active control during 12 months of follow-up.

Methods: In a randomized clinical trial with three parallel arms, participants were randomized to MI (N=257), usual case management (N=266), or an active control group (N=252). MI consisted of two MI sessions while the active control involved two sessions without MI, both were offered in addition to usual case management. The primary outcome was number of sickness absence days based on registry data. Secondary outcomes included time to sustainable RTW, defined as four consecutive weeks without medical benefits.

Results: The median number of sickness absence days for the MI group was 73 days [interquartile range (IQR) 31-147], 76 days (35-134) for usual care, and 75 days (34-155) for active control. In total 89%, 88% and 86% of the participants, respectively, achieved sustainable RTW. The adjusted hazard ratio (HR) for time to sustainable RTW was 1.12 (95% CI 0.90-1.40) for MI compared to usual case management and HR 1.16 (95% CI 0.93-1.44) compared to the active control.

Conclusions: This study did not provide evidence that MI offered by NAV caseworkers to sick-listed individuals was more effective on RTW than usual case management or an active control. Providing MI in this context could be challenging as only half of the MI group received the intervention.

Figure 1

Flow of participants through the study. ^a Reasons for not receiving MI intervention: already returned to work=20, illness=6, no time/not possible to manage=4, pregnant=3, language problems=2, no appointment made by case worker =4, other=4, unknown=60. Reasons for only receiving one MI session: already returned to work=3, illness=1, no appointment made by case worker =1, unknown=14. ^b Reasons for not receiving active control: already returned to work=18, Illness=5, no time/not possible to manage=6, no appointment made by case worker =5, pregnant= 3, language problems=3, other=4, unknown=56. Reasons for only receiving one session: Already returned to work=17, Illness=1, no time/not possible to manage=1, other=5, unknown=24. ^c Due to miscommunication, registry data was not obtained on five participants.

Figure 2

Cumulative number of workdays (median) on medical benefits for the motivational interviewing, usual case management and active control group during 12 months of follow-up, based on intention to treat analyses. Number of days are adjusted for employment fraction and transformed to whole workdays according to a 5-day workweek

Figure 3

Survival curves from the Kaplan Meier intention to treat analysis showing time to sustainable return to work (ie, 1 month not receiving medical benefits) for the motivational interviewing, usual case management and active control group during 12 months of follow-up.