Table 3: Mean costs in Euro (€) with 95% Confidence IntervalsB 3 months prior to, during, and 6 months after multidisciplinary rehabilitation in various clinical subgroups; the costs are presented according to the four cost groups.

Cost groupPre rehab stayRehabilitation stay0–3 months post rehab stay4–6 months post rehab stayP-value2

Inflamm. disease hospital ( 𝑛 = 4 8 ) 1378 (88–422)545 (87–595)586 (110–649).16
22,010 (−1,258–2,776)11,884 (10,940–13,443)3,808 (961–7,334)1,073 (−1,475–1521).61
3640 (−172–850)544 (261–587)1,136 (190–1492)1,136 (190–1492).45*
418,191 (3,209–9,039)3,158 (2,559–3,296)8,480 (3,721–9,335)8,480 (3,721–9,335).59*

Inflamm. disease outpatient hospital ( 𝑛 = 1 4 ) 1518 (248–645)652 (164–731)600 (69–715).54
21,448 (−1,991–2,385)2,309 (1,628–2,374)851 (−1,347–2,172)85 (−2,035–104).40
3636 (−786–1,458)371 (62–440)637 (−813–1498)637 (−813–1498)1.000*
416,059 (−532–8,516)2,437 (1,891–2,522)7,583 (1,410–9,849)7,583 (1,410–9,849).20*

Inflamm. disease rehab centre ( 𝑛 = 5 0 ) 1483 (362–606)830 (626–1,035)802 (595–1,009).01
21,411 (160–2,663)5,010 (4,703–5,316)522 (83–961)814 (−236–1,865).74
3232 (−69–534)665 (545–786)231 (−64–526)231 (−64–526).76*
419,637 (7,571–11,704)4,773 (4,451–5,004)10,215 (8,263–12,167)10,215 (8,263–12,167).77*

OA conventional rehab centre ( 𝑛 = 6 3 ) 1479 (181–533)897 (302–1,074)990 (201–1,367).005
22,629 (−691–3,447)4,780 (4,098–4,855)165 (−767–238)1,070 (−1,410–714).01
373 (−530–72)587 (336–600)72 (−518–71)72 (−518–71).65*
417,997 (3,058–8,703)4,608 (4,074–4,679)9,191 (4,589–9,888)9,191 (4,589–9,888).24*

OA postsurgery rehab ( 𝑛 = 1 3 1 ) 1415 (138–448)1,009 (498–1,112)659 (225–678)<.001
217,268 (17,142–19,899)3,704 (3,065–3,733)1,207 (−67–1,603)579 (−1,656–714)<.001
399 (−542–108)430 (187–433)89 (−505–91)89 (−505–91).002*
414,863 (438–5,176)3,636 (3,161–3,648)6,153 (1,854–6,549)6,153 (1,854–6,549).21*

Cost groups 1–4 refer to costs related to health consumption in the primary healthcare services (cost group 1), secondary healthcare services (cost group 2), use of medication (cost group 3), and costs related to production loss in terms of sick leave (cost group 4). All costs are presented in Euros: 1€ = 8 NOK.
OA: osteoarthritis; rehab: rehabilitation
B = Bootstrap 95% confidence interval.
1Production loss includes only sick leave for employed patients. Age and disability pension are not included.
2P-values refer to testing for differences between the three time periods 3 months prior to, 0 to 3 months, and 4 to 6 months after rehabilitation stay within each of the clinical subgroups and cost group. Rank sum based on “Kruskal-Wallis equality-of-populations rank test” was used.