A Naturalistic Trial of Nudging Clinicians in the Norwegian Sickness Absence Clinic. The NSAC Nudge Study (NSAC)

A Naturalistic Trial of Nudging Patients and Clinicians in the Norwegian Sickness Absence Clinics- The NSAC Nudge Study

The Norwegian Sickness Absence Clinic (NSAC) Nudge Study is a naturalistic randomized controlled multicentre trial which aim is to measure the efficacy of nudging clinicians' attention towards patients' motivation for work, barriers for return to work and work environment challenges, on functional recovery as primary outcome, and health outcomes as secondary outcome.

Patients will be recruited in five different NSACs across northern Norway. In total 1100 patients will be randomized to two equal probability treatment arms: 1) NSAC with the nudge, and 2) NSAC without the nudge. The nudge is tailored to the individual patient's needs using survey, and the clinicians are presented with a summary of this patient survey prior to consultations highlighting health problems and challenges as reported by the patient in the survey.

Study Overview

• Status: Active, not recruiting
• Conditions: Depression; Pain; Fatigue; Anxiety Disorders; Occupational Exposure; Musculoskeletal Disorder; Work Related Stress; Return to Work; Employment; Workplace Bullying; Sickness Absence
• Intervention / Treatment: Other: NSAC health only; Other: NSAC health + MBW

Detailed Description

The NSAC Nudge Study is part of a broader project, the Norwegian Sickness Absence Clinic Study (NSACS). The NSACS has two sources of funding (Northern Norway Regional Health Authority and The Norwegian Labour and Welfare Administration (NAV)), and involves two RCTs (NSAC Nudge and NSAC Efficacy) and fifteen work packages covering aspects of efficacy, interactions in efficacy, scalability, health economics, and characteristics of the target group and the patient group. The randomized controlled trial (RCT) NSAC Nudge is the subject of this trial registration. A list of the associated work-packages (WPs) is available in the protocol attached this registration at a later time point.

The NSAC Nudge Study is a randomized controlled multicentre trial, carried out in northern Norway and involving 5 Norwegian Sickness Absence Clinics (NSAC [Helse i Arbeid]). The study will recruit 1100 patients, randomized in equal proportions to either of two treatment arms 1) Treatment at the NSAC following a patient survey of health problems and 2) treatment at the NSAC following a patient survey of health problems as well as a survey on motivation for work, barriers for return to work and work environment (MBW).

The NSACs are staffed by teams of medical doctors specializing in physical medicine and rehabilitation, psychologists, physiotherapists and employment support supervisors. The NSAC service aims to provide quick clarification of health problems or treatment to patients with common mental disorders or musculoskeletal health problems with the goals of functional improvement, prevention of long-term sickness absence and return to work.

All patients are asked to fill out an online survey about their health and MBW factors between time of referral and their first treatment. The survey will also handle randomization. The NSAC clinicians are given a summary to be used in the treatment of the individual patient, and the effect of this comprehensive mapping and the provision of a condensed report to clinician prior to consultation is the primary aim of the RCT. The clinicians will be trained in how providing this information is going to guide clinical practice and using this information in treatment of patients.

The anticipated mechanism of the nudge is 1) an increased expectation among patients that MBW factors will be addressed during treatment, and/or 2) an increased focus on MBW factors by clinician in treatment, both due to the report and the patients' expectations. Whether this mechanism has an effect on patients' return to work (RTW) outcomes, prevention of sickness absence and general alleviation of symptoms will also be explored.

The data necessary to answer the research questions are gathered from national registries via personal identifier, registry data on population level, questionnaires filled out by the patient (data on health and working conditions) and questionnaires filled out by the clinician after each consultation (data on number of treatments, diagnosis, professions involved and types of treatment provided).

The patient questionnaire is divided in two surveys; 1) a health survey and 2) a survey on health and MBW. The health survey covers health, and includes musculoskeletal problems, mental health and other health related issues (such as alcohol consumption, medication and physical activity). The MBW survey includes working conditions (including inter alia questions on social support, work/family conflict and bullying), barriers for RTW, labour market affiliation, other personal aspects (such as demography and motivation for work), questionnaires for health economic evaluation and expectations for treatment.

By and large the questionnaire consists of test batteries which have been validated for specific topics. In an effort to reduce the number of questions posed to each patient, the baseline questionnaire will employ index questions which have proven psychometric properties in terms of factor loading or similar, meaning that if a problem on a specific topic such as neck pain is not indicated, the patient will not be presented with the Neck Disability Index questionnaire. The patient questionnaires will be filled out electronically after referral and prior to first treatment (Baseline, Time 0), as well as at 6 months after baseline (Time 1). We planned for a 12-month follow-up survey, but because of a technical error this second survey was never sent to participants. Accordingly the second follow-up survey will be sent to participants ultimo June 2024, which is in the interval between 17- and 31 months (depending on date of recruitment) after time of baseline survey (Time 2).

In the NSAC Nudge Study, receiving treatment at NSAC (Norwegian name HiA) does not presuppose consent to participate in research, but a mapping of health status is nevertheless a mandatory part of treatment. However, participation in research requires sharing these data and access to registry-based data for the involved patients.

• Study Type: Interventional
• Enrollment (Actual): 1180
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Norway
  • Nordland
    • Bodø, Nordland, Norway, 8092
      • Helse I Arbeid Nordlandssykehuset
    • Sandnessjøen, Nordland, Norway, 8800
      • Helse I Arbeid Helgelandssykehuset
  • Troms Og Finnmark
    • Alta, Troms Og Finnmark, Norway, 9510
      • Opptreningssenteret i Finnmark
    • Kirkenes, Troms Og Finnmark, Norway, 9915
      • Helse I Arbeid Finnmarkssykehuset
    • Tromsø, Troms Og Finnmark, Norway, 9019
      • Helse I Arbeid Universitetssykehuset Nord-Norge

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 23 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• For the study, the single inclusion criteria is that the patient is offered a consultation or treatment at the NSAC (Norwegian: HiA).

Exclusion Criteria:

• Aged younger than 23 years at time of referral. The NSACs have guidelines that describe eligibility for treatment, and excludes patients that are either too healthy for the measure, too sick for the measure, not relevant diagnosis or otherwise not considered being in the target group for the measure.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: NSAC health only; Treatment as usual (TAU) at NSAC, following a digital survey of health problems and the provision of a condensed report of this survey to clinician prior to consultation.	Other: NSAC health only; NSAC is an outpatient service delivered under the auspices of the specialist health care sector to patients currently on sick leave or at risk for long-term sickness absence. The service is staffed by medical doctors specialising in musculoskeletal health, physiotherapists, psychologists and welfare sector counsellors, and aims to provide patients with multi-disciplinary treatment with the intent of functional recovery. In "NSAC health only", clinicians are provided survey information on potential health problems only.
Experimental: NSAC health + MBW; Treatment as usual (TAU) at NSAC, following a digital survey of health problems as well as Motivation, Barriers for return to work and Work environment (MBW), and the provision of a condensed report of this survey to clinician prior to consultation.	Other: NSAC health + MBW; NSAC is an outpatient service delivered under the auspices of the specialist health care sector to patients currently on sick leave or at risk for long-term sickness absence. The service is staffed by medical doctors specialising in musculoskeletal health, physiotherapists, psychologists and welfare sector counsellors, and aims to provide patients with multi-disciplinary treatment with the intent of functional recovery. In "NSAC health + MBW" clinicians are provided survey information on potential health problems as well as information on motivation for work, barriers for return to work and work environment factors.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Functional recovery: status, plan and prognosis for employment versus sickness absence	Clinician report at last consultation of current status, plan and prognosis for patient employment versus sickness absence. Status is current employment versus sickness absence, plan refers to patients own ambition and plans for employment versus sickness absence short term, while prognosis refers to the clinicians assessment of prognosis for employment versus sickness absence in 12 months.	At last appointment at NSAC (can vary substantially between patients, but generally < 3 months after first appointment at NSAC)
Functional recovery: sickness absence self-report	Employment, sickness absence and application for rehabilitation benefits between Time 0 and Time 2, based on patient self-report.	Up to 31 months post baseline survey
Functional recovery: sickness absence registry data	Employment, sickness absence and application for rehabilitation benefits during first 365 days post baseline survey, based on registry data.	12 months post baseline survey
Functional recovery: disability benefits	Employment, sickness absence, rehabilitation benefits and disability benefits during 5-year period post baseline survey, all based on registry data.	60 months post baseline survey

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mental health	Changes in self-reported mental health between Time 0 and Time 1, and between Time 0 and Time 2, measured using the Hopkins Symptoms Checklist - 10 (HSCL-10).	Up to 31 months post baseline survey
Anxiety	Changes in self-reported anxiety between Time 0 and Time 1, and between Time 0 and Time 2, measured using the Beck Anxiety Inventory (BAI). The instrument is provided to patients upon indication, defined as a HSCL-10 score > 1.4	Up to 31 months post baseline survey
Depressive symptoms	Changes in self-reported depression between Time 0 and Time 1, and between Time 0 and Time 2, measured using the Beck Depression Inventory (BDI). The instrument is provided to patients upon indication, defined as a HSCL-10 score > 1.4	Up to 31 months post baseline survey
Sleep	Changes in self-reported sleep between Time 0 and Time 1, and between Time 0 and Time 2, measured using 3 questions commonly used to diagnose sleeping disorder according to the DSM-IV criteria for insomnia.	Up to 31 months post baseline survey
Health Anxiety	Changes in self-reported health anxiety between Time 0 and Time 1, and between Time 0 and Time 2, measured using the Whitely Index. All patients are asked the first question in the test battery, and the entire instrument is provided to patients with a score of >3 on this question	Up to 31 months post baseline survey
Subjective health complaints	Changes in subjective health between Time 0 and Time 1, and between Time 0 and Time 2, measured using a modified version of the Ursin Health Inventory.	Up to 31 months post baseline survey
Back pain	Changes in self-reported back pain Time 0 and Time 1, and between Time 0 and Time 2, measured using the Oswestry Disability Index (ODI). All patients are asked whether they suffer from musculoskeletal pain, and if present, they are provided questions on localization of pain. In case of back pain, patients are provided the ODI.	Up to 31 months post baseline survey
Neck pain	Changes in self-reported neck pain between Time 0 and Time 1, and between Time 0 and Time 2, measured using the Neck Disability Index (NDI). All patients are asked whether they suffer from musculoskeletal pain, and if present, they are provided questions on localization of pain. In case of neck pain, patients are provided the NDI.	Up to 31 months post baseline survey
Pain intensity	Changes in self-reported pain intensity between Time 0 and Time 1, and between Time 0 and Time 2, measured using a visual analogue scale scored between 0 and 10. All patients are asked whether they suffer from musculoskeletal pain, and if present, they are provided questions on pain intensity during rest and activity.	Up to 31 months post baseline survey
Fear avoidance	Changes in self-reported fear avoidance between Time 0 and Time 1, and between Time 0 and Time 2, measured using the Fear Avoidance Beliefs Questionnaire (FABQ). All patients are asked whether they suffer from musculoskeletal pain, and if present, they are provided the FABQ.	Up to 31 months post baseline survey
Physical activity	Changes in self-reported level of physical between Time 0 and Time 1, and between Time 0 and Time 2, measured using the Saltin-Grimby Physical Activity Level Scale (SGPALS).	Up to 31 months post baseline survey
Fatigue	Changes in self-reported fatigue between Time 0 and Time 1, and between Time 0 and Time 2, measured using the Fatigue Assessment Scale. All patients are asked the first question in the test battery, and the entire instrument is provided to patients with a score of ≥ 3 on this question	Up to 31 months post baseline survey
Pain localization	Changes in self-reported localization of pain between Time 0 and Time 1, and between Time 0 and Time 2. All patients are asked whether they suffer from musculoskeletal pain, and if present, they are provided questions on localization of pain.	Up to 31 months post baseline survey
Cause of pain	Changes in self-reported cause of pain between Time 0 and Time 1, and between Time 0 and Time 2. All patients are asked whether they suffer from musculoskeletal pain, and if present, they are provided questions on the believed cause of pain.	Up to 31 months post baseline survey
Self-reported diagnoses	Changes in self-reported diagnoses between Time 0 and Time 1, and between Time 0 and Time 2. The respondent is asked whether he/she thinks they have Covid-19 sequelae, myalgic encephalomyelitis/chronic fatigue syndrome, whiplash, fibromyalgia, hypermobility, irritable bowel syndrome or food intolerance, or whether they have been diagnosed with either of these by health personnel.	Up to 31 months post baseline survey

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Preventive effect of sickness absence	Changes in self-reported beliefs about the potential preventive effect of short-term sickness absence on long term sickness absence between Time 0 and Time 1, and between Time 0 and Time 2. The respondent is asked whether he/she agrees to 5 different statements on this topic, using a 5-point likert scale.	Up to 31 months post baseline survey
Health economic evaluation: self report	Health economic evaluation is measured using the EQ-5D and the ReQol instruments, issued to patients at baseline (Time 0) and at Time 1 and Time 2, to assess change.	Up to 31 months post baseline survey
Health economic evaluation: labour costs	Health economic evaluation also involves data on number of professions seeing the patient and number of working hours spent on the patient by each profession seeing the patient during the treatment period, recorded in questionnaires filled out by the clinicians after each consultation. This enables calculation of costs in terms of manpower and staff.	12 months post baseline survey
Expectations to- and evaluation of treatment	Using open-ended questions, patients are asked about their expectations towards treatment prior to first treatment, and about their evaluation of treatment 6- and 12 months first treatment. These two will be compared.	Up to 31 months post baseline survey
Barriers for return to work	Changes in self-reported barriers for return to work between Time 0 and Time 1, and between Time 0 and Time 2. The questionnaire includes 26 items concerning barriers for return to work and is part of the survey in the MBW intervention.	Up to 31 months post baseline survey
Motivation for work	Changes in self-reported motivation for work between Time 0 and Time 1, and between Time 0 and Time 2. The questionnaire consists of a number of questions concerning motivation, and is part of the survey in the MBW intervention.	Up to 31 months post baseline survey
Effort/reward imbalance	Changes in self-reported effort/reward imbalance between Time 0 and Time 1, and between Time 0 and Time 2. Effort/reward imbalance is part of the survey in the MBW intervention, and is measured using the 3 items with the highest factor loading in the Siegrist Effort/Reward Imbalance Questionnaire (short version). A high score on either of the three items triggers the rest of the questionnaire.	Up to 31 months post baseline survey
Workplace bullying	Changes in self-reported workplace bullying between Time 0 and Time 1, and between Time 0 and Time 2. Workplace bullying is measured using the Short Negative Acts Questionnaire (SNAQ).	Up to 31 months post baseline survey
Economic situation	Changes in self-reported economic situation between Time 0 and Time 1, and between Time 0 and Time 2. The questionnaire includes 2 items concerning economic problems and concerns about economic problems.	Up to 31 months post baseline survey
Procedural justice	Changes in self-reported procedural justice between Time 0 and Time 1, and between Time 0 and Time 2. Procedural justice is part of the survey in the MBW intervention, and is measured by 3 items concerning workplace decisions.	Up to 31 months post baseline survey
Relational justice	Changes in self-reported relational justice between Time 0 and Time 1, and between Time 0 and Time 2. Relational justice is part of the survey in the MBW intervention, and is measured by 4 items concerning the general behaviour of the respondent's supervisor.	Up to 31 months post baseline survey
Job phobia	Changes in self-reported job phobias between Time 0 and Time 1, and between Time 0 and Time 2. Job phobia is measured by 12 items concerning the respondent's avoidance of the workplace or work-related anxiety.	Up to 31 months post baseline survey
Ergonomic work environment	Changes in self-reported ergonomic work environment between Time 0 and Time 1, and between Time 0 and Time 2. Ergonomic work environment is measured by 11 items concerning the respondent's physical tasks at work.	Up to 31 months post baseline survey
Organisational change	Changes in self-reported organisational change between Time 0 and Time 1, and between Time 0 and Time 2. Organisational change is part of the survey in the MBW intervention, and is measured using the 3 items covering changes in management, colleagues and tasks.	Up to 31 months post baseline survey
Work/family conflict	Changes in self-reported work/family conflict between Time 0 and Time 1, and between Time 0 and Time 2. Work/family conflict is part of the survey in the MBW intervention, and is measured using the 4 items with the highest factor loading in the Home-Work Interference Scale.	Up to 31 months post baseline survey
Demand and control	Changes in self-reported demand and control between Time 0 and Time 1, and between Time 0 and Time 2. Demand and control is measured using three questions from the instrument developed by Karasek/Theorell, and is part of the survey in the MBW intervention. A high score on either of the three items triggers the rest of the questionnaire.	Up to 31 months post baseline survey

Collaborators and Investigators

• Sponsor: Nordlandssykehuset HF
• Collaborators: University Hospital of North Norway; UiT The Arctic University of Norway; Finnmarkssykehuset HF (Kirkenes, Norway); Opptreningssenteret i Finnmark (Alta, Norway); Helgeland Hospital Trust
• Investigators: Principal Investigator: Arnstein Mykletun, PhD, UiT The Arctic University of Norway

Publications and helpful links

General Publications

• Myhrer M, Brinchmann B, Trichet L, Aars NA, Mykletun A. Barriers for return to work as an iatrogenic effect of sickness absence: a proposed conceptual framework and questionnaire based on a cross-sectional study. BMC Public Health. 2026 Feb 12. doi: 10.1186/s12889-026-26584-1. Online ahead of print.
• Bardal I, Aars NAP, Trichet LO, Brandseth OL, Terjesen C, Irgens E, Hansen BO, Kristoffersen A, Hoper A, Jenssen OR, Brinchmann B, Mykletun A. Expanding the Focus on Work Factors in an Outpatient Setting: Does a Nudge of Patients and Clinicians have an Effect on Return-to-Work and Benefits? Findings from the NSAC Nudge Multicentre Randomised Controlled Trial. J Occup Rehabil. 2025 Dec 12. doi: 10.1007/s10926-025-10343-x. Online ahead of print.
• Aars NA, Bardal I, Brinchmann B, Mykletun A. Naturalistic trial of nudging patients and clinicians in the Norwegian sickness absence clinics: a study protocol for the NSAC Nudge Study. BMJ Open. 2025 Mar 3;15(3):e089758. doi: 10.1136/bmjopen-2024-089758.

Study record dates

Study Major Dates

• Study Start (Actual): September 6, 2021
• Primary Completion (Estimated): April 12, 2028
• Study Completion (Estimated): January 12, 2033

Study Registration Dates

• First Submitted: August 9, 2021
• First Submitted That Met QC Criteria: August 9, 2021
• First Posted (Actual): August 16, 2021

Study Record Updates

• Last Update Posted (Actual): April 13, 2026
• Last Update Submitted That Met QC Criteria: April 7, 2026
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: Return to work; Nudge; Sickness absence; Bullying; Barriers for return to work; Motivation for work; Demand and control; Work/family conflict
• Additional Relevant MeSH Terms: Neurologic Manifestations; Mental Disorders; Behavioral Symptoms; Stress, Psychological; Occupational Diseases; Aggression; Pathological Conditions, Signs and Symptoms; Behavior; Signs and Symptoms; Social Behavior; Harassment, Non-Sexual; Occupational Stress; Pain; Anxiety Disorders; Depression; Fatigue; Musculoskeletal Diseases; Bullying
• Other Study ID Numbers: NSAC Nudge

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: There are no plans to share individual patient data with other researchers. At the stage of analyses, associated researchers will be provided with an anonymized data set including all relevant data to answer the research questions.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No