You are here

Article Text

Article menu
Clinical and epidemiological research
Extended report
Reasons for medical help-seeking behaviour of patients with recent-onset arthralgia
  1. Jessica A B van Nies1,
  2. Elisabeth Brouwer2,
  3. Diederik P C de Rooy1,
  4. Floris A van Gaalen1,
  5. Tom W J Huizinga1,
  6. Marcel D Posthumus2,
  7. Annette H M van der Helm-van Mil1
  1. 1Department of Rheumatology, Leiden University Medical Center, Leiden, The Netherlands
  2. 2Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center, Groningen, The Netherlands
  1. Correspondence to Jessica A B van Nies, Department of Rheumatology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands; j.a.b.van_nies{at}lumc.nl

Abstract

Objective Patient delay in seeking medical help may cause suboptimal use of the therapeutic window in rheumatoid arthritis. We aimed to assess the motivations and the urgency with which patients with arthralgia seek medical help.

Methods 612 patients with arthralgia—visiting two Dutch Early Arthritis Recognition Clinics—were studied. Patients filled out a questionnaire with questions on their symptoms and their reasons for seeking medical help. Comparisons were made for patients with short or prolonged patient delay, patients with and without arthritis, age and gender.

Results The median symptom duration was 4 weeks. A prolonged delay in seeking help was associated with a gradual onset of symptoms (78%) and the perception that symptoms would not be serious or would go away (16% and 48%, respectively). Arthralgia patients who promptly sought medical help more often had an acute onset of symptoms and more frequently reported impairments at work or in daily functioning than patients who postponed seeking help (all p<0.005). Patients with and without arthritis generally had similar reasons for seeking help. The proportion of patients who had a prolonged patient delay was comparable between male and female subjects and between age categories. Particularly younger patients postponed seeking help because they thought their symptoms would disappear spontaneously.

Conclusions This large-scale study observed several reasons and symptom characteristics influencing the help-seeking behaviour of persons with arthralgia. These data can be helpful to define strategies aiming at early identification of arthritis.

  • Epidemiology
  • Early Rheumatoid Arthritis
  • Patient perspective

https://doi.org/10.1136/annrheumdis-2012-201995

Statistics from Altmetric.com

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

    Introduction

    Data of multiple observational cohorts and clinical trials indicate that treatment initiation in the first 3 months of rheumatoid arthritis (RA) is particularly effective at controlling arthritis and results in a better outcome.1–6 To allow early treatment initiation, it is required that arthritis is recognised at a very early stage.7 The time between symptom onset and the first visit to the rheumatologist is composed of several components, such as delay on part of the patient in seeking medical help at symptom onset, delay in referral by the general practitioner (GP) and delay in getting access to rheumatological care.8 This study evaluated reasons of patients with arthralgia for seeking medical help in the primary healthcare. Understanding the motivations leading to a delay in seeking medical help is required when considering targeted health interventions (directed at early recognition of arthritis) on the level of the general public.

    A recent study across Europe showed that the contribution of the patient delay to the total delay in RA varies from place to place. For instance, in Heraklion and Birmingham the median patient delay was 30 and 12 weeks, respectively, whereas in Vienna, Berlin and Warsaw the patient delay was relatively short (median 2–6 weeks).9 In a recent Dutch study, a median patient delay of 3.3 weeks was observed.10 Cultural differences or differences in design or the access to the healthcare system might contribute to the observed variations in patient delay.8 ,11

    The help-seeking behaviour of RA patients has been studied before and was recently summarised.12 Former studies had relatively small sample sizes (on average 30 patients per study, minimum 3, maximum 120 patients) and studied patients classified with RA who had variable disease durations (1–15 years). None of the previous studies evaluated drivers or barriers for seeking help at the stage of arthralgia.12 The present large-scale study was conducted to assess the reasons why patients with arthralgia seek medical help and to determine the readiness with which they seek medical help.

    Patients and methods

    Arthralgia patients

    We studied patients with arthralgia who were referred to one of our two Early Arthritis Recognition Clinics (EARC). These clinics were initiated in September 2010 in Leiden and in October 2010 in Groningen, The Netherlands. These outpatient clinics aim to decrease the GP delay.13 Our observation that in The Netherlands, GP delay contributed for two-thirds to the total delay and GPs frequently ‘wait-and-see’ in case they are unsure about the presence of arthritis, which prompted us to initiate the EARC.10 For further details on the design of the EARC please see13. At the EARC, patients were asked to fill out a questionnaire with questions on their symptoms, their functioning and their reasons for seeking medical help. Subsequently, they were screened for the presence of arthritis by a physical examination by experienced rheumatologists. In case of arthritis observed by the physical examination (this was found in 44.4% of cases), patients visited the general outpatient clinic within 1 week for further examinations (such as laboratory and radiological evaluations) and appropriate treatment.14 All arthralgia patients who were seen in our EARCs during the first 15 months were included.

    Questionnaire

    The questionnaire consisted of questions about several items. First, there were questions about the characteristics of the symptoms (pain, swelling or stiffness of joints experienced by the patient), the acuteness of onset, the distribution of the symptoms and the presence of morning stiffness. The dates of symptom onset (reported by the patient) and of the first visit to the GP were determined. Second, there were questions related to work absenteeism, presenteeism (reduced functioning while being at work) and the presence of impairments in daily functioning. Patients filled out a Health Assessment Questionnaire (HAQ). Finally, motivations for seeking medical help or postponing seeking medical help were evaluated. Patients were asked to indicate whether one or more reasons (presented in a list) were applicable to them; multiple answers were allowed (for the questions see online supplementary table 1). The questionnaire was completed by the patients without interference from the rheumatologist.

    The patient delay was defined as the period between symptom onset and the first visit to the GP. This delay is a composite of delay on the part of the patient in seeking medical help by a GP and the time a patient has to wait to see his/her GP after an appointment is made. In the Dutch healthcare system, patients have direct access to GPs, and so the latter part of this delay is negligible. Of all 612 patients, 125 patients did not report the first visit to the GP, so the duration of the patient delay could not be determined. Patients without data on the first GP visit were older (55.8 vs 49.2 years), less often had arthritis (32% vs 48%), less often had acute onset of symptoms (16% vs 37%) and had a significantly longer total delay (median 167 vs 12 weeks) than patients who did report the date of their first GP visit. Out of all patients with arthritis (n=272), there were 40 patients who did not report a date on the first GP visit. These patients were older (58 vs 51 years) and had a longer total delay (144 vs 8 weeks) than arthritis patients who did report the date of the first GP visit.

    Statistical analyses

    We started with an analysis of all arthralgia patients’ data. Subsequently, analyses were repeated for patients with short and prolonged patient delay, patients with and without arthritis and for gender and age categories (<40, 40–60 and >60 years).

    Comparisons were made using the χ2 test, Student t test or Mann–Whitney U test and Kruskal–Wallis test as applicable.

    Then we studied whether certain symptom characteristics and reasons for seeking medical help frequently occurred together. This was done at the variable level using the variable reduction technique Partial Least Squares regression (PLS). PLS combines variables that frequently occur together in the so-called latent factors. Age, gender, symptom characteristics, work-related questions and reasons for seeking help were included in the PLS as independent variables; the patient delay (short/prolonged) was entered as a dependant variable. Identified latent factors were plotted to look for clustering. To perform PLS, the relevant SPSS extension packages were downloaded from the official SPSS website. SPSS software V.17.0 was used. p Values <0.05 were considered significant.

    Results

    Arthralgia patients

    In total, 612 patients with arthralgia were evaluated; arthritis was observed in 272 patients (44.4%). Baseline characteristics are presented in table 1. The median patient delay was 4.1 (0.9–17.14) weeks. Overall, 24% of the patients were absent from work due to their symptoms and 61.7% of the patients experienced impairments in daily functioning (table 2). Frequently mentioned motivations to seek medical help were worsening of symptoms (66%) and impairments in daily functioning (35%). A frequent reason to postpone seeking medical help was the thought that symptoms would go away by themselves (39%) (table 3). Only 14% of the patients with arthralgia were concerned about having joint inflammation and knew that, in that case, they had to act quickly (table 3). The reasons for seeking medical help or postponing seeking medical help did not differ between the centres (data not shown). Therefore, we combined the datasets from both EARCs for this study.

    View this table:
    Table 1

    Baseline characteristics of all arthralgia patients as well as separated for short and prolonged patient delay and for patients with and without arthritis

    View this table:
    Table 2

    Frequency of absenteeism, impairment in work or in functioning in all arthralgia patients as well as separated for short and prolonged patient delay and for patients with and without arthritis

    View this table:
    Table 3

    Frequency of reasons for seeking medical help in all arthralgia patients and subsequently for short versus prolonged patient delay and patients with and without arthritis

    Comparisons for short versus prolonged patient delay

    Subsequently, patients with a short or prolonged patient delay were studied separately. Categorisation into ‘short delay’ and ‘prolonged delay’ was done using the median symptom duration at evaluation (4 weeks) as cut-off. Patients with a short patient delay more often experienced a sudden onset of symptoms than patients with prolonged delay (p<0.05 table 1). They also had a higher Health Assessment Questionnaire score, were more frequently absent from work (36% vs 14.4%, p<0.001), had more often functional impairment at work (70% vs 56%, p=0.006) as well as impairments in daily functioning (71% vs 54%, p=0.001). Furthermore, arthralgia patients with a short delay more frequently mentioned suddenly occurring symptoms and functional impairments as important reasons for rapidly seeking medical help (48% vs 18% and 41% vs 29%, respectively, p<0.05, table 3). Patients with a prolonged patient delay postponed seeking medical help because they thought the symptoms would go away by themselves or that the symptoms did not indicate anything serious. In all, 69% of the patients with a prolonged delay sought medical help because the symptoms were getting worse (table 3).

    Comparisons between patients with and without arthritis

    The median patient delay in the arthralgia patients who also had arthritis was 2.6 (0.7–9.0) weeks and 5.9 (1.1–27.9) weeks in the patients without arthritis (p<0.001) (table 2). Generally speaking, the reasons of patients with and without arthritis were not different, though patients with arthritis were more often motivated to seek medical help because they experienced symptoms that occurred suddenly (34% vs 23%, p<0.05) and, interestingly, also because they were more often advised to do so by family or friends (26% vs 19%, p<0.05, table 3).

    Comparisons between female and male subjects

    Overall, 70% of the arthralgia patients were female subjects. The median patient delay was 3.1 (0.9–12.9) weeks in male subjects and 4.3 (1.0–19.6) weeks in female subjects (not statistically significant). More male than female subjects were absent from their work due to the symptoms (31% vs 21%, p=0.033, table 4). Female subjects more often reported occurrence of new symptoms (41% vs 29%, p=0.005) and worsening of symptoms (69% vs 58%, p=0.015) as reasons for seeking medical help. Male subjects were more often concerned about the cause of the complaints (49% vs 39%, p=0.034, table 5). There were no differences in reasons for postponing seeking medical help.

    View this table:
    Table 4

    Frequency of absenteeism, impairment in work or in functioning in female and male patients and in patients in different age categories

    View this table:
    Table 5

    Frequency of reasons for seeking medical help in female and male patients and in patients in different age categories

    Comparisons between different age categories

    Patients with arthralgia were divided into three age categories based on the distribution of the raw data (not shown) as follows: <40 years (26%), 40–60 years (44%) and >60 years (30%). The median duration between symptom onset and first visit to the GP was 4.0 (1.1–12.6), 4.3 (1.0–21.9) and 3.3 (0.4–15.1) weeks, respectively. Patients in the youngest age category more frequently sought medical help because they experienced suddenly occurring symptoms (table 5). They were also more encouraged by family and friends to seek medical help (32.9% vs 17.4% and 20.1%, p=0.001). Patients in the oldest age category more often mentioned the wish for asking a painkiller as a reason for seeking medical help. With regard to reasons for postponing seeking medical help, arthralgia patients in the youngest age category more often thought that the symptoms would go away by themselves (51.3% vs 39.3% and 29.3%, p<0.001).

    Clustering of variables

    We subsequently questioned whether some symptom characteristics, motivations or variables concerning the ability to work frequently occurred together, thus clustering in the same arthralgia patients. A data reduction method, PLS regression analysis, was applied to this end. Two latent factors were found that together accounted for 33% of the observed variation (see online supplementary table 2). In figure 1, the individual patient scores on these factors were plotted against each other. Two clusters were observed. A group of patients was found who were characterised by a short patient delay, a sudden onset of symptoms, functional impairments and absenteeism. The other group consisted mainly of patients with a prolonged patient delay, a gradual onset of symptoms and no absenteeism.

    Figure 1
    Figure 1

    Clustering of variables in arthralgia patients related to help-seeking behaviour. In this plot each dot indicates a single person. Latent factor scores indicate how strongly each factor is represented in each patient. Patients with a patient delay <4 weeks are blue, whereas patients with a patient delay >4 weeks are green. The first latent factor is plotted on the y-axis, and the second latent factor is plotted on the x-axis. A group of patients (below y=0) was found who mostly had a short patient delay, had more often a sudden symptom onset, more functional impairments and were more often absent from work. The other group (above y=0) consisted mainly of patients with a prolonged patient delay, a gradual onset of symptoms and less absent from work.

    Discussion

    This study aimed to assess reasons of persons with arthralgia for seeking medical help. For early recognition of arthritis, it is required that such patients seek timely medical help. Comprehension of the symptoms or reasons that motivate persons with arthralgia to seek or postpone seeking medical help is crucial. It may be helpful in developing intervention strategies for public health. In the present study, 612 patients with arthralgia for whom the GP was unsure of the presence of arthritis were evaluated. The median duration between symptom onset and seeking help with the GP was relatively short (4 weeks) and was comparable with the patient delay that we observed recently in early RA patients who visited our early arthritis clinic.10 Despite the short patient delay on a group level, several symptom characteristics and reasons were associated with the readiness of seeking medical help. Most importantly, prolonged delay in seeking help was associated with a gradual onset of symptoms and the perception that symptoms were not serious and would go away by themselves. Arthralgia patients who rapidly sought medical help more often did so because symptoms suddenly occurred, because they had functional impairments and because they were absent from work due to their symptoms.

    Musculoskeletal problems are very common among the general population.15 ,16 A large population-based survey (3664 respondents) on musculoskeletal pain in The Netherlands showed that only about half of the persons consulted a health professional.16 This is consistent with a report on an Austria's initiative, the ‘Rheuma-bus’; here they found that about 40% of persons with musculoskeletal complaints never contacted a physician.17 The present study focused on patients who did seek medical help, although with differences in the readiness to do so. The present study is the first to evaluate patients with arthralgia instead of patients who are identified with RA. However, our study was not designed to identify the motivations of patients with musculoskeletal pain who did not seek medical help.

    The present study has several strengths. The patients studied had symptoms for (on average) a relatively short period. This indicates that the arthritis patients included in the present study were studied at a very early disease stage, earlier than has been studied thus far. The short symptom duration may also have reduced possible recall bias. Another strength of this study is the sample size, which is considerably larger than other studies on this subject9 and also allowed for performing subanalyses.

    Interestingly, the reasons for seeking medical help of patients with and without arthritis were not evidently different. It is noteworthy that in all subcategories studied, about two-thirds of the patients reported impairments in daily functioning as well as functional impairments at work. In about half of these patients (35%), these functional impairments were mentioned as a reason for seeking medical help.

    This study also has limitations. A limitation is that we did not use a validated questionnaire since such a questionnaire on this topic does not yet exist. It is reassuring that some of the findings of the present study are in line with previous, smaller studies. For instance, the association between impairment in daily functioning and a short patient delay has been observed before.11 ,18–20 At present, a questionnaire is being developed and validated that will assess reasons for delay in RA patients as well as in inflammatory arthritis patients.21 It would be very interesting to use this questionnaire in arthralgia patients as well. Arthralgia patients were not asked about their socio-economic status and educational level. This might also be considered a limitation.

    Importantly, only 14% of all arthralgia patients were aware that, in the presence of arthritis, it is relevant to act quickly. A lack of knowledge on arthritis and RA has also been observed previously in patients diagnosed with RA in the UK and Canada.11 ,19 ,20 This might call for a need for public health intervention strategies. When designing such strategies, the results of the present large-scale study may be helpful. A gradual onset of arthralgia and the perception that these symptoms were not serious and would go away by themselves were the main reasons for waiting for seeking medical help. Based on these results, in particular at places where patient delay is an important contributor to the total delay, it may be relevant to inform the general public about the type of symptoms of arthralgia for which medical help should be sought immediately.

    References

    1. ↵
      1. Nell VP,
      2. Machold KP,
      3. Eberl G,
      4. et al
      . Benefit of very early referral and very early therapy with disease-modifying anti-rheumatic drugs in patients with early rheumatoid arthritis. Rheumatology (Oxford) 2004;43:906–14.
      OpenUrlAbstract/FREE Full Text
    2. ↵
      1. Quinn MA,
      2. Conaghan PG,
      3. Emery P
      . The therapeutic approach of early intervention for rheumatoid arthritis: what is the evidence? Rheumatology (Oxford) 2001;40:1211–20.
      OpenUrlAbstract/FREE Full Text
    3. ↵
      1. van Aken J,
      2. Lard LR,
      3. le Cessie S,
      4. et al
      . Radiological outcome after four years of early versus delayed treatment strategy in patients with recent onset rheumatoid arthritis. Ann Rheum Dis 2004;63:274–9.
      OpenUrlAbstract/FREE Full Text
    4. ↵
      1. Mottonen T,
      2. Hannonen P,
      3. Korpela M,
      4. et al
      . Delay to institution of therapy and induction of remission using single-drug or combination-disease-modifying antirheumatic drug therapy in early rheumatoid arthritis. Arthritis Rheum 2002;46:894–8.
      OpenUrlCrossRefPubMedWeb of Science
    5. ↵
      1. Quinn MA,
      2. Emery P
      . Window of opportunity in early rheumatoid arthritis: possibility of altering the disease process with early intervention. Clin Exp Rheumatol 2003;21(5 Suppl 31):S154–7.
      OpenUrlPubMedWeb of Science
    6. ↵
      1. Finckh A,
      2. Liang MH,
      3. van Herckenrode CM,
      4. et al
      . Long-term impact of early treatment on radiographic progression in rheumatoid arthritis: a meta-analysis. Arthritis Rheum 2006;55:864–72.
      OpenUrlCrossRefPubMedWeb of Science
    7. ↵
      1. Gerlag DM,
      2. Raza K,
      3. van Baarsen LG,
      4. et al
      . EULAR recommendations for terminology and research in individuals at risk of rheumatoid arthritis: report from the Study Group for Risk Factors for Rheumatoid Arthritis. Ann Rheum Dis 2012;71:638–41.
      OpenUrlAbstract/FREE Full Text
    8. ↵
      1. Villeneuve E,
      2. Nam JL,
      3. Bell MJ,
      4. et al
      . A systematic literature review of strategies promoting early referral and reducing delays in the diagnosis and management of inflammatory arthritis. Ann Rheum Dis 2013;72:1322.
      OpenUrlAbstract/FREE Full Text
    9. ↵
      1. Raza K,
      2. Stack R,
      3. Kumar K,
      4. et al
      . Delays in assessment of patients with rheumatoid arthritis: variations across Europe. Ann Rheum Dis 2011;70:1822–5.
      OpenUrlAbstract/FREE Full Text
    10. ↵
      1. van der Linden MP,
      2. le Cessie S,
      3. Raza K,
      4. et al
      . Long-term impact of delay in assessment of patients with early arthritis. Arthritis Rheum 2010;62:3537–46.
      OpenUrlCrossRefPubMedWeb of Science
    11. ↵
      1. Kumar K,
      2. Daley E,
      3. Khattak F,
      4. et al
      . The influence of ethnicity on the extent of, and reasons underlying, delay in general practitioner consultation in patients with RA. Rheumatology (Oxford) 2010;49:1005–12.
      OpenUrlAbstract/FREE Full Text
    12. ↵
      1. Stack RJ,
      2. Shaw K,
      3. Mallen C,
      4. et al
      . Delays in help seeking at the onset of the symptoms of rheumatoid arthritis: a systematic synthesis of qualitative literature. Ann Rheum Dis 2012;71:4937.
      OpenUrlAbstract/FREE Full Text
    13. ↵
      1. van Nies JA,
      2. Brouwer E,
      3. van Gaalen FA,
      4. et al
      . Improved early identification of arthritis: evaluating the efficacy of Early Arthritis Recognition Clinics. Ann Rheum Dis 2013;72:1295301.
      OpenUrlAbstract/FREE Full Text
    14. ↵
      1. de Rooy DP,
      2. van der Linden MP,
      3. Knevel R,
      4. et al
      . Predicting arthritis outcomes–what can be learned from the Leiden Early Arthritis Clinic? Rheumatology (Oxford) 2011;50:93–100.
      OpenUrlAbstract/FREE Full Text
    15. ↵
      1. Bot SD,
      2. van der Waal JM,
      3. Terwee CB,
      4. et al
      . Incidence and prevalence of complaints of the neck and upper extremity in general practice. Ann Rheum Dis 2005;64:118–23.
      OpenUrlAbstract/FREE Full Text
    16. ↵
      1. Picavet HS,
      2. Schouten JS
      . Musculoskeletal pain in the Netherlands: prevalences, consequences and risk groups, the DMC(3)-study. Pain 2003;102:167–78.
      OpenUrlCrossRefPubMedWeb of Science
    17. ↵
      1. Machold KP,
      2. Koller MD,
      3. Pflugbeil S,
      4. et al
      . The public neglect of rheumatic diseases: insights from analyses of attendees in a musculoskeletal disease awareness activity. Ann Rheum Dis 2007;66:697–9.
      OpenUrlAbstract/FREE Full Text
    18. ↵
      1. Schneider M,
      2. Manabile E,
      3. Tikly M
      . Social aspects of living with rheumatoid arthritis: a qualitative descriptive study in Soweto, South Africa–a low resource context. Health Qual Life Outcomes 2008;6:54.
      OpenUrlCrossRefPubMed
    19. ↵
      1. Townsend A,
      2. Adam P,
      3. Cox SM,
      4. et al
      . Everyday ethics and help-seeking in early rheumatoid arthritis. Chronic Illn 2010;6:171–82.
      OpenUrlAbstract/FREE Full Text
    20. ↵
      1. Sheppard J,
      2. Kumar K,
      3. Buckley CD,
      4. et al
      . ‘I just thought it was normal aches and pains’: a qualitative study of decision-making processes in patients with early rheumatoid arthritis. Rheumatology (Oxford) 2008;47:1577–82.
      OpenUrlAbstract/FREE Full Text
    21. ↵
      DELAY study. http://www.earlyarthritis.co.uk/home.htm (accessed 1 Oct 2011). Ref Type: Online Source.

    Supplementary materials

    • Supplementary Data

      This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.

      Files in this Data Supplement:

    Footnotes

    • Handling editor Tore K Kvien

    • Contributors JvN has made a substantial contribution to the acquisition, analysis and interpretation of the data and has been involved in drafting of the manuscript. EB has made a substantial contribution to the conception and design, acquisition of the data and revising the manuscript for important and intellectual content. DdR was involved in the analysis of the data. FvG was involved in the acquisition of the data and revising the manuscript. TH has been involved in revising the manuscript for important intellectual content. MP has made a substantial contribution to the acquisition of the data and revising the manuscript for important and intellectual content. AvdH made a substantial contribution to the conception and design, to the acquisition and interpretation of data and has been involved in drafting of the manuscript as well as revising the manuscript for important intellectual intellect.

    • Funding This work is supported by a grant of the Centre for Medical Systems Biology and by The European Community Seventh Framework Programme FP7 Health-F2-2008-223404 (Masterswitch) and by the IMI JU funded project BeTheCure, contract no 115142-2. The work of AHM van der Helm-van Mil is supported by a grant of the Dutch Organization of Health Research and Development.

    • Competing interests None.

    • Ethics approval The EARC is primarily part of our care. Patients visiting the EARC were not subjected to procedures that were done for scientific purposes, such as blood taking for biobanking. Since the EARC is patient care, patients do not need to sign an informed consent form; nonetheless, it is allowed that the clinical data of the patients screened at the EARC may be used (anonoymised) for evaluations as presented in the present manuscript. This is completely in line with the Dutch ‘Wet medisch-wetenschappelijk onderzoek met mensen’ (translated ‘act on scientific research with persons’) (http://www.ccmo-online.nl/main.asp?pid=43&thid=57&catid=2). Therefore, in line with the Dutch law, patients were not asked to sign an informed consent form.

    • Provenance and peer review Not commissioned; externally peer reviewed.

    Linked Articles