Economic Evaluations of Treatments for Fibromyalgia

Table 1. Characteristics of the included studies.
Authors, year, and language of publication	Interventions	Participants' characteristics*	Details of the economic evaluation	Outcomes, costs categories, and follow-ups
Goossens et al., 1996,¹⁰ English Support paper for data extraction: Vlaeyen et al., 1996⁵⁰	Educational cognitive group (ECO): received education and cognitive treatment (psychological intervention) Educational discussion group (EDI): received education and participated in a group discussion program Waiting list condition group (WLC): not described in the study	Age: ECO 44.6 years (9.3), EDI 44.6 years (9.6), WLC 42.8 years (9.6) Female: ECO 93%, EDI 87%, and WLC 82% Diagnostic criteria: ACR 1990Pain duration: ECO 10.4 years (7.7), EDI 10.2 years (8.8), WLC 9.9 years (7.9) Total sample size: 131	Country: Netherlands Currency: US Dollars Time horizon: 12 months Perspective: societal Type of economic evaluation: cost-utility analysis Willingness to pay: NR Reference year: 1993 Discounting: NA	QALY (Maastricht Utility Measurement Questionnaire, 0–1) Healthcare costs, patient and family costs, and lost productivity costs Follow-up at 12 months
Oliver et al., 2001,³⁴ English	Social support group (SS): received an intervention based on promoting empathy and sharing of coping techniques between group members Social support and education group (SSE): received social support and education Control group (CG): received no treatment	Age: SS 53.7 years (11.6), SSE 55.1 years (11), CG 52.9 years (11.7) Female: SS 95.5%, SSE 96.1%, CG 94.3% Diagnostic criteria: ACR 1990 Pain duration: SS 13.6 years (13.2), SSE 14.4 years (14.2), CG 11.7 years (12.1) Total sample size: 600	Country: United States Currency: US Dollars Time horizon: 12 monthsPerspective: healthcare (assumed) Type of economic evaluation: cost-effectiveness analysis (assumed) Willingness to pay: NR Reference year: 1996 (assumed) Discounting: NA	Impact of fibromyalgia (Fibromyalgia Impact Questionnaire, 0–100) Healthcare costs Follow-up at 12 months
Ziljstra et al., 2007,⁵⁵ English Support paper for data extraction: Ziljstra et al., 2005⁵⁴	Spa treatment group (SPA): received thalassotherapy, exercise, and education programme Control group (CG): received usual care	Age, median (range): SPA 48 years (22–64), CG 47 years (24–64) Female: SPA 95%, CG 96% Diagnostic criteria: ACR 1990 Years since continuous symptoms onset, median (range): SPA 10 (2–35), CG 10 (1–42) Total sample size: 134	Country: Netherlands Currency: Euros Time horizon: 12 months Perspective: societal Type of economic evaluation: cost-utility analysis Willingness to pay: NR Reference year: 2000 Discounting: NA	QALY (SF-6D, 0–1) Healthcare costs, patient and family costs, and lost productivity costs Follow-up at 12 months
Gusi and Tomas-Carus, 2008,¹¹ English	Exercise group (EG): received usual care and the addition of an aquatic exercise programme Control group (CG): received standard care	Age: EG 50.7 years (10.6), CG: 50.9 years (6.7) Female: 100% in both groups Diagnostic criteria: ACR 1990 Duration of symptoms: EG 20.1 years (8), CG 19.4 years (6.9) Total sample size: 33	Country: Spain Currency: Euros Time horizon: 8 months Perspective: healthcare and societal Type of economic evaluation: cost-utility analysis Willingness to pay:€23,153/QALY Reference year: 2005 Discounting: NA	QALY (EQ-5D, 0–1) Healthcare costs and patient and family costs Follow-up at 8 months
Luciano et al., 2013,²⁵ English Support paper for data extraction: Luciano et al., 2011²⁴	Intervention group (IG): received a psychoeducative program added to usual care (psychological intervention) Control group (CG): received usual care	Age: IG 55.2 years (8.6), CG 55.4 years (8.7) Female: IG 97.2%, CG 98.1% Diagnostic criteria: ACR 1990 Years of diagnosis: IG 15.2 (11.7), CG 14.3 (10.6) Total sample size: 216	Country: Spain Currency: Euros Time horizon: 12 months Perspective: healthcare and societal Type of economic evaluation: cost-utility analysis Willingness to pay: NR Reference year: 2008 Discounting: NA	QALY (EQ-5D, 0–1) Healthcare costs and patient and family costs Follow-up at 12 months
Luciano et al., 2014,²⁶ English Support paper for data extraction: Alda et al., 2011¹	Cognitive behavioural therapy group (CBT): received cognitive behavioural therapy intervention (psychological intervention) Food and Drug Administration–recommended pharmacological treatment group (RPT): received a pharmacological treatment Treatment-as-usual group (TAU): received standard care	Age: CBT 46.5 years (6.7), RPT: 47.1 (6.5), TAU: 47 (6.5) Female: CBT 94.7%, RPT 92.9%, TAU 96.4% Diagnostic criteria: ACR 1990 Mean years since diagnosis: CBT 12.9 (7.5), RPT: 11.2 (3.9), TAU 11.4 (4) Total sample size: 169	Country: Spain Currency: Euros Time horizon: 6 monthsPerspective: healthcare and societal Type of economic evaluation: cost-utility analysis Willingness to pay: NR Reference year: 2011 Discounting: NA	QALY (EQ-5D, 0–1) Healthcare costs and lost productivity costs Follow-up at 6 months
van Eijk-Hustings et al., 2016,⁴⁹ English Support paper for data extraction: van Eijk-Hustings et al., 2013⁴⁸	Multidisciplinary intervention group (MD): received sociotherapy, physical therapy, psychotherapy, and creative arts therapy Aerobic exercise group (AE): received aerobic exercise Usual care group (UC): received usual care	Age: MD 41.5 years (9.6), AE 41 years (9), UC 42.9 years (11) Female: MD 93.5%, AE 100%, UC 97.9% Diagnostic criteria: ACR 1990 Duration of fibromyalgia related symptoms before diagnosis: MD 6.9 years (6.2), AE 6.9 years (6.1), UC 7.1 years (6.4) Total sample size: 203	Country: Netherlands Currency: Euros Time horizon: 24 months Perspective: healthcare and societal (assumed) Type of economic evaluation: cost-effectiveness analysis (assumed) Willingness to pay: NR Reference year: 2010 Discounting: NR	Impact of fibromyalgia (Fibromyalgia Impact Questionnaire, 0–100) Healthcare costs and patient and family costs Follow-up at 24 months
Luciano et al., 2017,²⁸ English Support paper for data extraction: Luciano et al., 2014²⁷	Acceptance and commitment therapy group (ACT): received acceptance and commitment therapy (psychological intervention) Recommended pharmacological treatment group (RPT): received a pharmacological treatment Waiting list group (WL): received usual care	Age: ACT 48.9 years (6), RPT 47.8 years (5.0), WL 48.3 years (5.7) Female: ACT 96.1%, RPT 98.1%, WL 94.3% Diagnostic criteria: ACR 1990 Years of diagnosis: ACT 14.1 (9), RPT 11.4 (8), WL 13 (8.8) Total sample size: 156	Country: Spain Currency: Euros Time horizon: 6 months Perspective: healthcare and societal Type of economic evaluation: cost-utility and cost-effectiveness (assumed) analyses Willingness to pay: NR Reference year: 2014 Discounting: NA	QALY (EQ-5D, 0–1) Impact of fibromyalgia (Fibromyalgia Impact Questionnaire, 0–100) Healthcare costs and lost productivity costs Follow-up at 6 months
Hedman-Lagerlof et al., 2019,¹⁴ English Support paper for data extraction: Hedman-Lagerlof et al., 2018¹³	Internet-delivery exposure therapy group (iExp): received psychoeducation exposure to fibromyalgia-related and pain-related stimuli, and mindfulness (psychological intervention) Waiting list control group (WLC): received no treatment	Age: iExp 51.8 years (10.7), WLC 49.3 years (10) Female: iExp 97%, WLC 99% Diagnostic criteria: made by a physician Years with diagnosis: iExp 11 (7.3), WLC 9.2 (7.5) Total sample size: 140	Country: Sweden Currency: US Dollars Time horizon: 3 months Perspective: healthcare and societal Type of economic evaluation: cost-utility and cost-effectiveness analyses Willingness to pay: NR Reference year: 2016 Discounting: NR	QALY (EQ-5D, 0–1) Impact of fibromyalgia (Fibromyalgia Impact Questionnaire, 0–100) Healthcare costs, patient and family costs, and lost productivity costs Follow-up at 3 months
Pérez-Aranda et al., 2019,³⁵ English Support paper for data extraction: Pérez-Aranda et al., 2019³⁶	Mindfulness-based stress reduction added to treatment-as-usual group (MBSR): received a transdiagnostic mindfulness–based intervention FibroQoL added to treatment-as-usual group (FibroQoL): received psychoeducation and self-hypnosis (psychological intervention) Treatment-as-usual group (TAU): continued regular pattern of medication	Age: MBSR 52.6 years (8), FibroQoL 54.4 years (7.7), TAU 53.2 years (8.4) Female: MBSR 97.1%, FibroQoL 98.5%, TAU 98.5% Diagnostic criteria: ACR 1990 Years of diagnosis: MBSR 14.5 (9.2), FibroQoL 11.3 (7.2), TAU 13.7 (10) Total sample size: 204	Country: Spain Currency: Euros Time horizon: 12 months Perspective: healthcare and societal Type of economic evaluation: cost-utility analysis Willingness to pay: €25,000/QALY Reference year: 2016 Discounting: NA	QALY (EQ-5D, 0–1) Healthcare costs and lost productivity costs Follow-up at 12 months
D'Amico et al., 2020,⁸ English Support paper for data extraction: Montero-Marin et al., 2018³²	Attachment-based compassion therapy added to treatment-as-usual group (ABCT): received mindfulness and self-compassion Relaxation group (REL): received relaxation (intervention of both groups was considered as psychological)	Age: ABCT 50.8 (8.7), REL 52.2 (6) Female: ABCT 100%, REL 100% Diagnostic criteria: ACR 1990 Years of diagnosis: NR Total sample size: 42	Country: Spain Currency: Euros Time horizon: 3 months Perspective: healthcare Type of economic evaluation: cost-utility and cost-effectiveness (assumed) analyses Willingness to pay: NR Reference year: 2016 Discounting: NA	QALY (EQ-5D, 0–1) Impact of fibromyalgia (Fibromyalgia Impact Questionnaire, 0–100) Healthcare costs Follow-up at 3 months

*Data presented as mean (SD), unless when stated.
ACR, American College of Rheumatology; EQ-5D, EuroQol-5 dimension; NA, not applicable; NR, not reported; QALY, quality-adjusted life-year; SF-6D, Short-Form 6 Dimension.

Table 2. Assessment of the consolidated health economic evaluation reporting standards statement for the included economic evaluations.
Study	Items
Study	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	Overall score (0–24)
Goossens et al.¹⁰	Y	N	Y	Y	Y	Y	Y	Y	NA	Y	Y	Y	Y	Y	NA	NA	N	NA	N	N	NA	N	Y	N	13 Y, 6 N, 5 NA
Oliver et al.³⁴	Y	N	Y	Y	Y	N	Y	Y	NA	Y	Y	NA	Y	N	NA	NA	Y	NA	N	N	NA	N	Y	N	11 Y, 7 N, 6 NA
Ziljstra et al.⁵⁵	Y	N	N	Y	Y	Y	Y	Y	NA	Y	Y	Y	Y	Y	NA	NA	Y	NA	Y	Y	NA	Y	Y	Y	17 Y, 2 N, 5 NA
Gusi and Tomas-Carus¹¹	Y	N	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	NA	NA	Y	NA	Y	Y	NA	Y	Y	Y	19 Y, 1 N, 4 NA
Luciano et al.²⁵	Y	N	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	NA	NA	Y	NA	Y	Y	NA	N	Y	Y	18 Y, 2 N, 4 NA
Luciano et al.²⁶	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	NA	NA	Y	NA	Y	Y	NA	N	Y	Y	19 Y, 1 N, 4 NA
Van Eijk-Hustings et al.⁴⁹	Y	N	Y	Y	Y	N	Y	Y	N	Y	Y	NA	Y	Y	NA	NA	Y	NA	N	N	NA	Y	Y	Y	14 Y, 5 N, 5 NA
Luciano et al.²⁸	Y	N	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	NA	NA	Y	NA	Y	Y	NA	N	Y	Y	18 Y, 2 N, 4 NA
Hedman-Lagerlof et al.¹⁴	Y	N	Y	Y	Y	Y	Y	Y	NA	Y	Y	N	Y	Y	NA	NA	Y	NA	Y	Y	NA	Y	Y	Y	17 Y, 2 N, 5 NA
Pérez-Aranda et al.³⁵	Y	N	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	NA	NA	Y	NA	Y	Y	NA	Y	Y	Y	19 Y, 1 N, 4 NA
D'Amico et al.⁸	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	NA	NA	Y	NA	Y	Y	NA	Y	Y	Y	20Y, 4 NA

1: title, 2: abstract, 3: background and objective, 4: target population and subgroups, 5: setting and location, 6: study perspective, 7: comparators, 8: time horizon, 9: discount rate, 10: choice of health outcomes, 11: measurement of effectiveness, 12: measurement and valuation of preference-based outcomes, 13: estimating resources and costs, 14: currency, price date, and conversion, 15: choice of model, 16: assumptions, 17: analytic models, 18: study parameters, 19: incremental costs and outcomes, 20: characterizing uncertainty, 21: characterizing heterogeneity, 22: study findings, limitations, generalizability, and current knowledge, 23: source of funding, 24: conflicts of interest.
Y, yes; N, no; NA: not applicable.

Table 3. Risk of bias assessment of the randomized controlled trials.
Study	Domain
Study	Bias arising from the randomization process	Bias due to deviations from intended interventions	Bias due to missing outcome data	Bias in measurement of the outcome	Bias in selection of the reported result	Overall risk of bias judgement
Goossens et al.¹⁰	High	High	High	High	Low	High
Oliver et al.³⁴	High	High	High	High	Low	High
Ziljstra et al.⁵⁵	Low	High	High	High	Low	High
Gusi and Tomas-Carus¹¹	High	Some concerns	Low	High	Low	High
Luciano et al.²⁵	High	Some concerns	Low	High	Low	High
Luciano et al.²⁶	Low	Some concerns	Low	High	Low	High
Van Eijk-Hustings et al.⁴⁹	Low	Some concerns	High	High	Low	High
Luciano et al.²⁸	Low	Some concerns	Low	High	Low	High
Hedman-Lagerlof et al.¹⁴	Low	Some concerns	Low	High	Low	High
Pérez-Aranda et al.³⁵	High	Some concerns	High	High	Low	High
D'Amico et al.⁸	Low	Some concerns	Low	High	Low	High

Table 4. Results of the included studies.
Study	Intervention (sample size)	Costs, mean (SD), incremental costs (95% CI)		Effects, mean (SD)*, incremental effects (95% CI)	ICER
Study	Intervention (sample size)	Healthcare perspective	Societal perspective	Effects, mean (SD)*, incremental effects (95% CI)	ICER
Goossens et al.¹⁰	Educational cognitive group (ECO), n = 49 Educational discussion group (EDI), n = 39	Costs ECO† $3542 (NR)/€3013 (NR) Costs EDI $2395 (NR)/€2037 (NR) Incremental costs‡ $1147/€976	Costs ECO† $17,238 (NR)/€14,663 (NR) Costs EDI $13,698 (NR)/€11,651 (NR) Incremental costs‡ $3540/€3011	QALY effects ECO: NR EDI: NR Incremental QALY effects: 0.027 (NR)	Healthcare $42,487 or €36,140/QALY Societal $131,122 or €111,532/QALY§
Oliver et al.³⁴	Social support group (SS), n = 200 Social support and education group (SSE), n = 207 Control group (CG), n = 193	Costs SS $6763 (6578)/€5753 (5596) Costs SSE $7126 (9061)/€6061 (7707) Costs CG $6849 (12,959) €5826 (11,023) Incremental costs SS vs SSE\|\| $−363 (−1897 to 1172) €−309 (−1614 to 997) Incremental costs SS vs CG $−86 (−2129 to 1957) €−73 (−1811 to 1665) Incremental costs SSE vs CG $277 (−1929 to 2483) €236 (−1641 to 2112)	Not collected	IF effects SS: 54.70 (18.00) SSE: 56.00 (16.50) CG: 58.30 (17.30) Incremental IF effects\|\| SS vs SSE: −1.30 (−4.66 to 2.06) SS vs CG: −3.60 (−7.09 to −0.11) SSE vs CG: −2.30 (−5.62 to 1.02)	Not calculated because the sample size for costs and effects is different. ICER was also not presented in the study.
Ziljstra et al.⁵⁵	Spa treatment group (SPA), n = 58 Control group (CG), n = 76	Costs SPA $5733 (2902)/€4738 (2399) Costs CG $3457 (5113)/€2857 (4226) Incremental costs $2276 (−60 to 4090) €1881 (−50 to 3380)	Costs SPA $12,600 (NR)/€10,414 (NR) Costs CG $10,511 (NR)/€8687 (NR) Incremental costs Societal‡: $2090/€1727	QALY effectsSPA: 0.610 (0.080) CG: 0.610 (0.070) Incremental QALY effects\|\|: 0.000 (−0.030 to 0.030)	Not calculated because the incremental QALY is 0
Gusi and Tomas-Carus¹¹	Exercise group (EG), n = 17 Control group (CG), n = 16	Costs EG: NR Costs CG: NR Incremental costs:$791 (NR)/€647 (NR)	Costs EG: NR Costs CG: NR Incremental costs:$1580 (NR)/€1291 (NR)	QALY effects EG: 0.133 (NR) CG: 0.002 (NR) Incremental QALY effects: 0.131 (0.011 to 0.290)	Healthcare $6041 or €4936/QALY Societal $12,061 or €9853/QALY
Luciano et al.²⁵	Intervention group (IG), n = 108 Control group (CG), n = 108	Costs IG $2073 (1910)/€1624 (1496) Costs CG $2717 (2140)/€2128 (1676) Incremental costs $−327 (−933 to 437) €−256 (−731 to 342)	Costs IG $2789 (3124)/€2184 (2447) Costs CG $3339 (3082)/€2615 (2414) Incremental costs $−299 (−1191 to 600) €−234 (−933 to 470)	QALY effects IG: NRCG: NR Incremental QALY effects: 0.120 (0.060 to 0.190)	Healthcare: IG dominant Societal: IG dominant
Luciano et al.²⁶	Cognitive behavioural therapy group (CBT), n = 57 Food and Drug Administration–recommended pharmacological treatment group (RPT), n = 56 Treatment-as-usual group (TAU), n = 56	Costs CBT $2000 (3998)/€1552 (3102) Costs RPT $4176 (6075)/€3240 (4713) Costs TAU $3464 (5212)/€2688 (4044) Incremental costs CBT vs RPT $−2634 (−4068 to −1199) €−2043 (−3156 to −930) Incremental costs CBT vs TAU $−2383 (−4007 to −760) €−1849 (−3109 to −590) Incremental costs RPT vs TAU $250 (−1514 to 2015) €194 (−1175 to 1563)	Costs CBT $2696 (4296)/€2092 (3333) Costs RPT $5349 (6627)/€4150 (5141) Costs TAU $4560 (5770)/€3538 (4477) Incremental costs CBT vs RPT $−3365 (−4856 to −1873) €−2610 (−3768 to −1453) Incremental costs CBT vs TAU $−3152 (−4901 to −1402) €−2445 (−3802 to −1088) Incremental costs RPT vs TAU $213 (−1680 to 2106) €166 (−1303 to 1634)	QALY effects CBT: 0.250 (0.120) RPT: 0.230 (0.130)TAU: 0.240 (0.130) Incremental QALY effects CBT vs RPT: 0.010 (0.000 to 0.030) CBT vs TAU: 0.020 (0.000 to 0.030) RPT vs TAU: 0.000 (0.010 to 0.020)	CBT vs RPT Healthcare: CBT dominant Societal: CBT dominant CBT vs TAU Healthcare: CBT dominant Societal: CBT dominant RPT vs TAU¶ Healthcare$143,701 or €111,488/QALY Societal$115,434 or €89,557/QALY
Van Eijk-Hustings et al.⁴⁹	Multidisciplinary intervention group (MD), n = 108 Aerobic exercise group (AE), n = 47 Usual care group (UC), n = 48	Costs MD $5196 (NR)/€4068 (NR) Costs AE $5320 (NR)/€4166 (NR) Costs UC $5625 (NR)/€4405 (NR) Incremental costs MD vs AE $−124 (−1266 to 1321) €−97 (−991 to 1034) Incremental costs MD vs UC $−429 (−1679 to 896) €−336 (−1314 to 701) Incremental costs AE vs UC $−305 (−1787 to 1193) €−239 (−1399 to 934)	Costs MD $7017 (NR)/€5494 (NR) Costs AE $6397 (NR)/€5008 (NR) Costs UC $6295 (NR)/€4928 (NR) Incremental costs MD vs AE $620 (−2028 to 709) €486 (−1588 to 555) Incremental costs MD vs UC $722 (−619 to 2158) €566 (−485 to 1690) Incremental costs AE vs UC $102 (−1517 to 1779) €80 (−1188 to 1393)	IF effects MD: 50.90 (2.00) AE: 52.00 (3.20) UC: 56.20 (2.90) Incremental IF effects\|\| MD vs AE: −1.10 (−2.09 to −0.11) MD vs UC: −5.30 (−6.20 to −4.40) AE vs UC: −4.20 (−5.43 to −2.97)	MD vs AE Healthcare: MD dominant Societal $−564 or €−442/IF MD vs UC Healthcare: MD dominant Societal $−136 or €−107/IFAE vs UC Healthcare: AE dominant Societal$−24 or €−19/IF§
Luciano et al.²⁸	Acceptance and commitment therapy group (ACT), n = 51 Recommended pharmacological treatment group (RPT), n = 52 Waiting list group (WL), n = 53	Costs ACT $1200 (1547)/€880 (1135) Costs RPT $2519 (2411)/€1848 (1770) Costs WL $3584 (4107)/€2630 (3014) Incremental costs ACT vs RPT $−1294 (−2248 to −339) €−949 (−1650 to −249) Incremental costs ACT vs WL $−2368 (−3653 to −1083) €-1738 (−2681 to −795) Incremental costs RPT vs WL $−1074 (−2525 to 377) €−788 (−1853 to 276)	Costs ACT $3300 (2596)/€2422 (1905) Costs RPT $3863 (3037)/€2835 (2229) Costs WL $6059 (4892)/€4447 (3590) Incremental costs ACT vs RPT $−567 (−1769 to 635) €−416 (−1298 to 466) Incremental costs ACT vs WL $-2704 (−4225 to −1182) €−1984 (−3101 to −867) Incremental costs RPT vs WL $−2137 (−3786 to −487) €−1568 (−2779 to −358)	QALY effects ACT: 0.340 (0.060) RPT: 0.330 (0.060) WL: 0.280 (0.070) Incremental QALY effectsACT vs RPT: 0.010 (0.000 to 0.030) ACT vs WL: 0.050 (0.040 to 0.070) RPT vs WL: 0.040 (0.020 to 0.050) IF effects ACT: 49.49 (8.77) RPT: 65.11 (8.87) WL: 67.45 (9.15) Incremental IF effects\|\| ACT vs RPT: −15.62 (−19.03 to −12.21) ACT vs WL: −17.96 (−21.40 to −14.52) RPT vs WL: −2.34 (−5.79 to 1.11)	ACT vs RPT Healthcare QALY: ACT dominant IF: ACT dominant§ Societal QALY: ACT dominant IF: ACT dominant§ ACT vs WL Healthcare QALY: ACT dominant IF: ACT dominant§ Societal QALY: ACT dominant IF: ACT dominant§ RPT vs WL Healthcare QALY: RPT dominant IF: RPT dominant§ Societal QALY: RPT dominant IF: RPT dominant§
Hedman-Lagerlof et al.¹⁴	Internet-delivery exposure therapy group (iExp), n = 70 Waiting list control group (WLC), n = 70	Costs iExp $3030 (3969)/€2199 (2881) Costs WLC $2858 (3550)/€2074 (2576) Incremental costs $773 (NR)/€561 (NR)	Costs iExp $9476 (8646)/€6878 (6275) Costs WLC $12,709 (12,595)/€9224 (9141) Incremental costs $−5349 (NR)/€−3882 (NR)	QALY effects iExp: 0.600 (0.300) WLC: 0.440 (0.320) Incremental QALY effects: 0.070 (NR) IF effects iExp: 36.44 (25.56) WLC: 57.71 (21.62) Incremental IF effects\|\|: −21.07 (−28.91 to −13.23)	Healthcare QALY $11,039 or €8012 IF: $−37 or €−27 Societal QALY: iExp dominant IF: iExp dominant
Pérez-Aranda et al.³⁵	Mindfulness-based stress reduction added to treatment-as-usual group (MBSR), n = 68 FibroQoL added to treatment-as-usual group, n = 68 Treatment-as-usual group (TAU), n = 68	Costs MBSR $1686 (1368)/€1224 (993) Costs FibroQoL $1896 (1272)/€1376 (923) Costs TAU $2331 (1845)/€1692 (1339) Incremental costs MBSR vs FibroQoL $−344 (−805 to 116) €−250 (−584 to 84) Incremental costs MBSR vs TAU $−664 (−1319 to −7) €−482 (−957 to −5) Incremental costs FibroQoL vs TAU $−320 (−957 to 318) €−232 (−695 to 231)	Costs MBSR $2271 (2372)/€1648 (1722) Costs FibroQoL $2938 (3094)/€2133 (2246) Costs TAU $3687 (4399)/€2676 (3193) Incremental costs MBSR vs FibroQoL $−787 (−1771 to 197) €−571 (−1285 to 143) Incremental costs MBSR vs TAU $−1207 (−2478 to 63) €−876 (−1798 to 46) Incremental costs FibroQoL vs TAU $−420 (−1907 to 1064) €−305 (−1384 to 774)	QALY effects MBSR: 0.540 (0.180) FibroQoL: 0.500 (0.200) TAU: 0.480 (0.220) Incremental QALY effects MBSR vs FibroQoL: 0.012 (−0.033 to 0.058) MBSR vs TAU: 0.053 (−0.004 to 0.102) FibroQoL vs TAU: 0.041 (−0.002 to 0.084)	MBSR vs FibroQoL Healthcare: MBSR dominant Societal: MBSR dominant MBSR vs TAU Healthcare: MBSR dominant Societal: MBSR dominant FibroQoL vs TAU Healthcare: FibroQoL dominant Societal: FibroQoL dominant
D'Amico et al.⁸	Attachment-based compassion therapy added to treatment-as-usual group (ABCT), n = 23 Relaxation group (REL), n = 19	Costs ABCT $961 (240)/€698 (174) Costs REL$1358 (317)/€986 (230) Incremental costs $−374 (−652 to −95) €−271 (−473 to −69)	Not collected	QALY effects ABCT: 0.17 (0.04) REL: 0.13 (0.06) Incremental QALY effects:0.021 (0.009 to 0.033) IF effects ABCT: 49.13 (15.07) REL: 67.82 (17.77) Incremental IF effects\|\|:−18.69 (−28.78 to −8.60)	Healthcare QALY: dominant IF: dominant§

CI, confidence interval; ICER, incremental cost effectiveness ratio; IF, impact of fibromyalgia; NR, not reported; QALY, quality-adjusted life-year.
*Higher scores for QALY and lower scores for impact of fibromyalgia indicate a better condition.
†The year considered for conversion was 1996 because data from 1993 (reference year of the paper) were not available in one conversion database.
‡Incremental costs were calculated as described in Methods.
§ICERs were calculated as described in Methods.
||Calculated using Review Manager version 5.3.
¶ICER was converted using the values presented in the article because it was not possible to recalculate as incremental QALY was 0.