The Impact of Income Support Systems on Healthcare Quality and Functional Capacity in Workers with Low Back Pain: A Realist Review

Background: Low back pain (LBP) is a leading cause of work disability. While absent from work, workers with LBP may receive income support from a system such as workers' compensation or social security. Current evidence suggests that income support systems can influence recovery from LBP, but provides little insight as to why and how these effects occur. This study examines how and in what contexts income support systems impact the healthcare quality for people with work disability and LBP and their functional capacity. Methods: We performed a realist review, a type of literature review that seeks to explain how social interventions and phenomena in certain contexts generate outcomes, rather than simply whether they do. Five initial theories about the relationship between income support systems and outcomes were developed, tested, and refined by acquiring and synthesising academic literature from purposive and iterative electronic database searching. This process was supplemented with grey literature searches for policy documents and legislative summaries, and semi-structured interviews with experts in income support, healthcare and LBP. Results: Income support systems influence healthcare quality through funding restrictions, healthcare provider administrative burden, and allowing employers to select providers. They also influence worker functional capacity through the level of participation and financial incentives for employers, measures to prove the validity of the worker's LBP, and certain administrative procedures. These mechanisms are often exclusively context-dependent, and generate differing and unintended outcomes depending on features of the healthcare and income support system, as well as other contextual factors such as socioeconomic status and labour force composition. Discussion: Income support systems impact the healthcare quality and functional capacity of people with work disability and LBP through context-dependent financial control, regulatory and administrative mechanisms. Research and policy design should consider how income support systems may indirectly influence workers with LBP via the workplace.


138
We conducted this review and report our findings as per Pawson's methodology and 139 the Realist And Meta-narrative Evidence Syntheses: Evolving Standards 140 9 healthcare quality for LBP or on the functional capacity of workers with LBP. Further 187 information on eligibility criteria is available in our protocol [32]. 188

Data extraction and appraisal
189 Data were extracted from each piece of literature by at least two authors into a 190 standardised data extraction table within a Microsoft Excel spreadsheet [49]. As well 191 as the characteristics of included studies (such as study region, sample 192 characteristics and data sources), we also extracted data in relation to each of the 193 five initial theories. The relevance and rigour of literature was rated as very, 194 moderately, or less relevant or rigorous. Relevance refers to whether literature 195 contains data that adequately addresses a theory, and rigour whether or not the data 196 were generated with "credible and trustworthy" methods [31,37,38]. These two 197 dimensions are typical of a realist review and are often used as a form of quality 198 appraisal, in place of traditional quality assessment or risk of bias tools [31,32]. 199 Semi-structured interviews 200 One author (MDD) conducted four semi-structured telephone interviews with experts 201 in the fields of income support systems, healthcare and LBP. Interviews were not 202 intended to be exhaustive but used to test our initial theories and identify important 203 anecdotal or experiential knowledge that might be lacking from traditional literature 204

searches. 205
The Monash University Human Ethics Research Committee provided ethics approval 211 for this project (Project ID 14144, July 2018). 212 213 Data generated from the different sources were combined and consolidated into 214 context-mechanism-outcome (CMO) configurations [31]. These CMO configurations 215 were first organised under each of the initial theories. Each member of the review 216 team independently reviewed CMO configurations and theories and then the findings 217 were discussed as a group to deliberate the role of context, the relevance and rigour 218 of evidence, and varying outcome patterns. The review team also decided whether 219 theoretical saturation had been reached and if subsequent further literature searches 220 were required to adequately explain a theory. The first author (MDD) compiled the 221 results of independent review and discussions, and refined the theories and CMO 222

Data analysis and synthesis
configurations. This synthesis process was performed four times, as theories were 223 refined. 224 Changes from protocol 225 Three minor changes were made to the methodology of the review compared to the 226 protocol. Firstly, an eligibility criterion was added before the commencement of full-227 functional capacity and healthcare quality. That is, they described simply that an 235 interaction occurs, and did not contribute to the refinement of our theories. 236 Secondly, we adopted citation searching during the review (described above), as it 237 was more efficient for iterative searches. Finally, due to time constraints we 238 conducted four semi-structured interviews rather than the planned ten to 15 [32]. 239 However, this was unlikely to effect the findings as the four interviews sufficiently 240 tested the initial theories. 241 CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.

Search results
is the (which was not peer-reviewed) The copyright holder for this preprint . 256 Details of the included studies is shown in Table 1. The majority of studies were 257 conducted in the US (n=13) and Canada (n=4). Other studies were published 258 variously in Japan (n=1), the UK (n=1) and Australia (n=1), with a single study 259 including six different countries (Denmark, Germany, Israel, the Netherlands, 260

Characteristics of included studies
Sweden, and the US). Most studies solely utilised administrative data (n=10), six 261 used administrative data and other data sources, five used questionnaire data alone, 262 while two reviews used academic literature. 263

[INSERT TABLE 1 AND CAPTION HERE] 264
Characteristics of included systems 265 Information on the system types of included studies is described in Table 2. Four 266 studies defined the typology of the disability policy model, employment injury 267 protection scheme, unemployment protection scheme and healthcare system [51-268 54]. There were a limited range of system types, as most studies were conducted in 269 North America. Most studies explored the impact of workers' compensation systems; 270 that is they explored the 'employer liability' type employment injury protection 271 scheme. This system is a cause-based system funded by insurance premiums from 272 employers. Three studies examined other system types, such as social security and 273 disability insurance (SSDI). These disability-based systems sit within a liberal 274 disability policy model and a social insurance unemployment protection scheme and 275 benefit applicants are typically means-tested [52,54]. 276 Most studies were conducted in environments with either a private healthcare 277 system or national health insurance system. Healthcare system type was defined by 278 state, societal or private responsibility for regulation, funding, and service provision 279 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
is the (which was not peer-reviewed) The copyright holder for this preprint . of healthcare. The US is one of a few systems where healthcare regulation, funding, 280 and service provision are private. Canada and Australia have a national health 281 insurance system in which regulation and funding are performed by the province or 282 state respectively, with private service provision [51,55] Table 3) 299

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Results of the analysis and synthesis are presented below and summarised in Figure  301 2. Each theory is supported by at least one CMO configuration. Where a single CMO 302 configuration supported a theory, the CMO configuration is reported as the theory. 303 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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[INSERT FIGURE 2 AND CAPTION HERE] 304
Theory 1 -Income support system role in funding healthcare 305 Income support systems that pay for and control healthcare in regions with 306 commodified healthcare systems can generate adverse healthcare and functional 307 outcomes for workers with LBP due to underlying financial incentives and healthcare 308 professional responses to funding restrictions, as well as healthcare provider peer 309 interactions, and regional socioeconomic factors. 310

CMO configuration 1 (n=3 pieces of literature) 311
In regions where income support systems can fund healthcare that would otherwise 312 be funded by insurance or out-of-pocket payments, healthcare professionals are 313 incentivised to provide unnecessary care. 314 Regions with a greater number of independent MRI sites had higher rates of early 315 MRI due to potential clinician 'self-referral' [33] Income support systems implement policy mechanisms and tools to control  328   healthcare expenditure with strategies such as medical fee schedules, utilization  329   review programmes, limiting treating provider choice and number of services.  330 However, these restrictions on healthcare payments can lead to either no change in 331 healthcare quality outcomes [33], diversion to other treatment options [20], or 332 negative healthcare quality outcomes such as increased opioid prescribing [58], 333 possible additional heath services [59] and poorer functional outcomes such as 334 increased length of disability [27]. The literature suggested that healthcare providers 335 -"increased the volume and complexity of treatment to maintain income levels" [27]. 336 However, a fee schedule by itself does not appear to trigger a healthcare provider to 337 demonstrate this behaviour [59]. Instead, the degree of restriction imposed by the 338 policy tends to correlate with more income-driven behaviour [59] author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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CMO configuration 4 (n=3 pieces of literature) 352
Healthcare providers in regions with lower socioeconomic status and fewer 353 healthcare resources select options that require less effort, consume fewer 354 resources and are not supported by best practice evidence. 355 Regional socioeconomic factors were demonstrated to affect healthcare provision 356 and length of disability in workers with LBP. Lower median household income was 357 associated with higher rates of early MRI (within 30 days), as clinicians chose the 358 "less time-and-effort-consuming" option of referring workers to imaging for LBP 359 rather than attempting to explain the condition to workers with potentially lower 360 education levels [33]. Household inequality was also associated with opioid 361 prescription, as it was thought that opioids were prescribed in place of access to 362 appropriate high-quality healthcare services in higher poverty areas [58]. Higher 363 unemployment rates were generally associated with a greater length of disability. 364 One offered explanation was that where unemployment is high workers have 365 difficulty finding alternative work that is less physically demanding [28]. 366 Theory 2 -Income support system demands on healthcare providers  Work-focussed healthcare is acknowledged as important for recovery among 374 workers with LBP among workers with LBP, yet some clinicians do not address this. 375 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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Evidence from a review suggests healthcare professionals regard work issues as 376 beyond their "professional remit" [60]. There was also evidence to suggest clinicians 377 who do not see work issues and return to work as part of their role may focus solely 378 on clinical issues [61]. A lack of experience with workers' compensation workers 379 may lead to worse worker outcomes [62], and minimal willingness to change 380 practices based on new work-focussed knowledge [63]. Expert interviewees agreed 381 with literature that healthcare professionals may not address work issues and 382 income support systems because of the perceived increased demands, and lack of 383 financial incentive, time, and decision-making authority [60]. However, a single study 384 also suggested that knowledge of patient workers' compensation status was unlikely 385 to affect clinical decision-making [57]. This also aligned with statements from expert 386 interviewees that even if healthcare providers are not incentivized to engage income 387 support systems, quality of care was unlikely to be affected. 388 Where income support systems allow the employer to choose the workers' 391 healthcare provider in regions with income support systems funded by employers, 392 the employer is incentivized by wage replacement and insurance premiums to 393 choose the healthcare provider that will return the worker to work the fastest. 394 In the US, the length of disability was lower when the employer could choose 395 healthcare providers, which was attributed to selection of work-focussed healthcare 396 providers who were familiar with the workplace [27]. This aligned with results from 397 interviews. The experts suggested this theory might hold, although the employer is 398 likely to focus on wage replacement duration as a function of total premium costs 399 and not healthcare quality. Experts further explained that employers in their 400 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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respective countries have little to no influence on healthcare. Further US literature 401 measured the effect of limiting treatment provider choice as part of a composite cost 402 containment score. While cost containment was shown to have an adverse effect on 403 healthcare quality and work outcomes, it was not possible to isolate treating provider 404 choice from the composite measure, and it is unclear how initial treating provider 405 choice contributed to this outcome [33,58]. 406 Where income support systems require employer involvement in worker 409 rehabilitation, penalties for non-compliance incentivise employers. 410

Theory 4 -Employer incentives
There was limited LBP-specific literature available for this theory, although expert 411 interviewees suggested that it may be possible. A single trial that found that the 412 introduction of an employer-based peer adviser led to a 49% reduction in LBP-413 related sick leave [63]. Legislation to increase worker functional accommodation was 414 followed by an increase in healthcare costs associated with no-loss-time claims [64]. 415 Experts suggested that a financial incentive may work in their own respective 416 systems, however the motivation would be for employers to return workers to work 417 and reduce their financial burden, not to improve their functional capacity. Another 418 expert pointed to a lack of financial incentive or motivation for employers to be 419 involved in worker recovery in some regions. A third expert suggested that some 420 employers may just 'tick the boxes' to meet legislative requirements until they can 421 terminate the worker's employment. 422 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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423
Where income support systems with more generous benefits require workers with 424 LBP to meet administrative requirements and prove the validity of their disability, 425 workers feel unsupported and are not incentivized to return to work. 426

CMO configuration 8 427
Income support systems that require workers to prove their injury when they have a 428 Where workers are required to prove they are disabled due to their LBP and 'defend 432 their legitimacy', they may have worse work outcomes. It is possible that the 433 presence of financial incentives motivate workers to have their disability recognised. 434 Interviewed experts suggested that where workers have to prove their LBP causes 435 disability (i.e., cause-based systems); they may seek tests that are more complex 436 and treatments to legitimize their pain with the income support system or employer. 437 Workers funded by workers' compensation tended to have worse functional 438 outcomes than workers funded by disability pensions or disability insurance (i.e., 439 where a specific cause is not required), and motor vehicle accident insurance [65-440 67]. In a motor vehicle accident compensation system, a switch from a tort to no-fault 441 scheme significantly reduced claims for LBP as well as the median duration of 442 disability [68]. These data conflicted with a single study. However, the latter study 443 compared types of benefits in a region with a disability-based income support 444 system, making comparisons challenging [69]. It was hypothesised that the 445 adversarial environment associated with tort law may delay claim closure. Experts 446 also noted that LBP tends to carry more stigma than other 'more credible' conditions, 447 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
is the (which was not peer-reviewed) The copyright holder for this preprint . and that the associated residual pain issues and diagnostic uncertainty can frustrate 448 workers. Nevertheless, one study comparing multiple countries demonstrated that 449 requirement for medical certification to receive benefits was not a significant 450 predictor of engagement in return to work [70]. 451

CMO configuration 9 (n=4 pieces of literature) 452
Income support systems that offer more generous benefits or who step down 453 benefits in response to return to work activities reduce the incentive for workers to 454 seek functional improvement, contributing to increased work absence. 455 Both literature and interviewed experts suggested that more 'benevolent' wage 456 replacement reduced the incentive for workers to return to work [60]. Wage 457 replacement that offered a higher proportion of the workers' pre-injury earnings and 458 reductions in benefits during scenarios such as partial return to work acted as 459 disincentives to return to work. Conversely, a single trial only found differences in 460 return to work between workers who do and do not receive workers' compensation 461 when they had surgical intervention for their LBP; no differences were found in those 462 conservatively managed [71]. The authors acknowledged the potential role of 463 financial incentives, but hypothesised that there may be other important differences 464 between compensated and non-compensated workers. Another study of a similar 465 cohort also identified significant differences in socioeconomic characteristics of 466 workers who did and did not receive workers' compensation [72]. The authors 467 suggested these should be considered when attempting to causally link 468 compensation and worker outcomes. An international-comparative study also 469 suggested that the absence of long-term disability benefits, or delayed access to 470 them, was predictive of earlier return to work [70]. The US interviewee also explained 471 that to avoid long-term liability associated with indefinite claims in some US states, 472 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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workers' compensation bodies had begun paying lump sums to some workers, 473 however, the effect of this was unknown. 474

CMO configuration 10 (n=1 piece of literature) 475
Income support systems that include certain administrative requirements that result 476 in waiting periods or delays and cause the worker to feel unsupported and frustrated, 477 leading to worse functional and recovery outcomes. 478 Certain 'rules and practices' of the system such as 'right to case appeal' and 'slow or 479 dissatisfactory case management' have been cited as detrimental to worker recovery 480 [60]. Interviewed experts suggested such features and waiting periods may stop the 481 worker from working, and that if the worker feels unsupported during these periods 482 they may be less likely to ultimately return to work. One expert also pointed to 483 requirements for approval for certain healthcare providers or volumes of healthcare 484 by some income support systems, possibly leading to worse functional outcomes. 485

486
This realist review sought to understand how and in what contexts income support 487 systems impact healthcare quality and functional capacity in workers with LBP. We 488 have found those healthcare providers, employers, and workers' responses to 489 income support system policies and features, can impact healthcare quality and 490 worker functional capacity. These effects are context specific and only operate in 491 certain types of income support and healthcare systems or in workers with certain 492 sociodemographic features. While contemporary literature has previously identified 493 the impact of income support systems on these outcomes, we believe this review 494 provides a new understanding of the causes of these events. 495 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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Trends in included literature and theories
496 Several trends emerged in the included literature. The use of a successionist model 497 of causality meant the majority of included studies treated income support systems 498 as single entities or statuses, which may miss certain nuances inherent to large 499 systems such as income support. The majority of included literature also did not 500 discuss context in detail, or even at all. In particular, there was limited discussion of 501 the context of parallel systems or regions. For example, few pieces of literature 502 investigating income support systems also described the local healthcare system 503 despite the potentially important relationship between the two. Finally, we found that 504 most literature originated in regions with similar system types. 505 Several theoretical themes were also present. We found the prevailing mechanisms 506 were economic incentives. The role of economic incentives in the income support 507 and healthcare system settings has long been documented [73][74][75][76][77]. Most policies of 508 income support systems rely on the responses of actors to economic incentives. In 509 some cases economic incentives lead to contradictory behaviour from system actors. 510 For example, the income maintenance strategy, theorised by some included studies, 511 was thought to be a direct response to attempts to reduce healthcare costs. 512 Supporting evidence from work disability literature not specific to 513 people with LBP 514 We identified some evidence that was ineligible for inclusion, but may have 515 contributed to the development and refinement of our theories. This evidence was 516 usually excluded as the sample did specifically include workers with LBP. For the 517 most part, work disability literature not specific to LBP aligns with our already 518 established theories. For example, healthcare providers have previously found 519 difficulties with workers' compensation systems and the return to work process in 520 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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workers who had "multiple injuries, gradual onset or complex illnesses, chronic pain, 521 and mental health conditions" [26]. In some cases healthcare providers were found 522 to refuse to treat compensated workers, citing additional "clinical complexities" and 523 "time and financial burdens" [78]. Such evidence aligns with our established Theory 524 2. However, additional insights indicate that differences in doctors' roles within 525 systems may affect work outcomes [79], financial incentives may be used 526 successfully to influence healthcare provider adoption of occupationally-focussed 527 healthcare programs [80], and fee schedules can achieve intended cost-containment 528 objectives [81]. Furthermore, a shift of funding income support responsibility from the 529 state to employers was found to be beneficial for worker return to work times [82]. 530 There is also evidence to suggest that specific financial incentives for employers 531 may encourage actions such as claim reporting time [83]. 532 The impact of the income support system directly on the worker is also well-533 documented, and aligns with our Theory 5. Evidence exploring the mechanisms and 534 contexts in which benefit generosity may have incentive effects and impact work 535 disability outcomes has previously been published [73][74][75][76][77]. There is also evidence to 536 suggest that receipt of financial compensation is associated with worse functional 537 outcomes [84]. More specifically, the administrative and legal aspects of income 538 support systems may be generally detrimental to recovery [85], and most 539 interactions with income support systems resulted in "significant psychosocial 540 consequences for injured workers" [25]. 541 However, we sought to identify and understand the impact of income support 542 systems specifically on outcomes of workers with LBP as this is the greatest 543 contributor to disability worldwide [4]. In the majority of cases it is not possible to 544 identify a specific pathoanatomic cause of LBP, and the diagnosis of non-specific 545 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
is the (which was not peer-reviewed) The copyright holder for this preprint . https://doi.org/10.1101/2020.01.13.20017343 doi: medRxiv preprint LBP typically depends upon ruling out much rarer specific and or serious causes. 546 The subjective nature and causative ambiguity of LBP appears to lend itself to a 547 certain amount of stigma or challenged integrity [86], that is not reflected in other 548 musculoskeletal conditions such as osteoarthritis [87]. This may lead to particular 549 challenges for a worker seeking wage replacement from a cause-based system. The 550 US interviewee even suggested worker attempts "to prove the legitimacy of their pain 551 and disability" might lead to greater utilisation of tests such as imaging, as reflected 552 in Theory 5. 553 The role of context and system types 554 The mechanisms identified in the review were conceptually reliant on underlying 555 contextual factors. There is likely substantial complexity to the number and layer of 556 contextual factors not elucidated in this review. However, we were able to 557 understand the theoretical influence that some high-level contextual factors, such as 558 system typology, had over some mechanisms. For example, the income 559 maintenance behaviour demonstrated by healthcare providers appears to be reliant 560 on a commodified healthcare system type [51,88]. 561 Healthcare system type is one feature of a larger policy landscape. Some included 562 literature suggested that different income support system types (i.e., cause-based or 563 disability-based systems) might lead to different outcomes. In one circumstance 564 disability-based systems such as unemployment benefits appeared to have better 565 outcomes than time-limited benefits [67]. Furthermore, it has previously been 566 suspected that the tightening of US workers' compensation policies lead workers to 567 move to social security disability insurance. That is, a move from cause-based 568 systems to a disability-based system. However, identifying causality for this inter-569 system movement has previously been debated [89,90]. 570 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
is the (which was not peer-reviewed) The copyright holder for this preprint . https://doi.org/10.1101/2020.01.13.20017343 doi: medRxiv preprint A strength of our realist review is that we used transparent methods and published 582 our protocol including our initial theories in an open peer-reviewed journal [32]. Our 583 protocol was peer-reviewed by two experts in realist reviews. As is customary for 584 realist reviews we used an iterative search strategy and searched both academic 585 and grey literature. We also documented all changes to our protocol including their 586 justification. 587 We also recognise several limitations of this review. We treated context at a very 588 high-level. By opting for system typologies, rather than more detailed features, we 589 avoided the impact of policy changes over time and differences in local applications. 590 However, this did prevent a more detailed understanding of the policy setting. 591 Included literature was published between 1988 and 2018. There has been 592 substantial development the evidence-base for LBP, as well as in the design of 593 income support systems, during this time. We did not account for this temporality 594 issue in our review. Finally, we also had a small and relatively homogenous sample 595 of expert interviewees. Although interviews were not the primary activity of this 596 review, we could have benefited from a larger and more role-diverse sample. 597 Recommendations for future policy development 624 While we acknowledge that policy development for LBP should be context 625 dependent, we can make some broad recommendations. Firstly, a biopsychosocial 626 approach, rather than a more typical economic approach, should be considered 627 when developing policies. 628

Recommendations for future research
The findings from our review confirm that there is interaction between different 629 systems. A disabled worker typically engages a healthcare and income support 630 system simultaneously; they require may treatment from the healthcare system to 631 return to work, utilising wage replacement from the income support system in the 632 interim. Any future policy development should therefore explore how policies within 633 one system may affect other systems. We also identified research of conditions other 634 than LBP to suggest that the policies of one income support system may affect 635 another income support system. Future policy development should not be performed 636 in 'silos', and instead consider wider societal and inter-system ramifications.

Availability of data and material 663
Literature included in this review is available through the relevant journals. 664 Transcripts of interviews conducted in this review are not publicly available. 665 . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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Competing interests 666
The authors declare that they have no competing interests. 667 CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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FIGURES AND TABLES
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CC-BY 4.0 International license
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is the

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The copyright holder for this preprint  It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
is the

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The copyright holder for this preprint Theory 5  Switch from tort to no-fault system decreased 6-month incidence of claims from 256 per 100,000 adults to 175 and 177 per 100,000 adults in first and second following months  Switch from tort to no-fault systems associated with decrease in median time to claim closure from 505 days to 216 and 203 days in first and second following months  'Adversarial environment' associated with tort law thought to delay claim closure and recovery  'When benefits are tied to pain and suffering, the insurance system acts in opposition to modern rehabilitation methods that emphasise mobility and ability over pain and disability'

APPENDIX
Appendix Table 3 Summary of results from semi-structured interviews Section Key points Theory 1  Should work in theory, probably does not in practice  Fee schedules are too limiting, do not always offer evidence-based care, and when they do practitioners might not adhere to guidelines anyway  In a private healthcare system, good providers might opt out of care if fee schedules are too low  Fee schedules could also be used to reduce inequalities between subgroups Theory 2  Volume of paperwork required by workers' compensation systems and a lack of decision-making authority were flagged as disincentives for healthcare providers to engage the system  This would not affect healthcare quality though Theory 3  Agreement that this might work in US  While the theory might hold, the employer is likely to focus on reducing wage replacement time and not healthcare quality  Employers have little to no say in healthcare in some jurisdictions Theory 4  Financial incentive could be good, but warned against over-estimating the effect it might have  Incentives are not based around worker recovery and functional capacity past what is required to return to work Theory 5  Experts suggested that functional capacity might not be the right outcome for this theory  There may be a lack of incentive or motivation for employers to be involved in worker recovery in the UK, as the state handles all wage replacement  This theory would hold, but there are changes in local legislation that might allow employers to 'tick the boxes' until they could remove an injured worker . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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The copyright holder for this preprint  All experts agreed with this theory  Experts suggested that longer wait times and a worker perception that they have to prove their injury is real, or feeling unsupported, questioned, or tested by the system, healthcare provider, or employer, leads to worse functional and recovery outcomes How do income support systems impact healthcare quality?
 The perception that workers need to prove that they are injured can lead them needing to feel 'sicker' and seek more aggressive treatment and diagnostics to prove their pain and have it documented  Specific characteristics of income support systems, such as the use of Independent Medical Examiners may lead to negative outcomes How do income support systems impact functional capacity?
 Some disorders might be more 'credible' than others; LBP tends to carry more stigma, residual pain issues, and diagnostic uncertainty that can make it frustrating for workers Other  More benevolent a wage replacement system, the less motivating it is to seek functional improvement  There has been a shift in the US toward lump sum payments to reduce long-term, sometimes indefinite, claim liability  It was also noted that a substantial volume of workers' compensation claims in the US may now be investigated by private investigators, and that it was commonplace for a worker with a low back pain claim to be filmed and this may have a negative impact on functional capacity and recovery . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
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The copyright holder for this preprint . CC-BY 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.