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Clinical and epidemiological research
Extended report
Lack of understanding in fibromyalgia and rheumatoid arthritis: the Illness Invalidation Inventory (3*I)
  1. M B Kool1,
  2. H van Middendorp1,
  3. M A Lumley2,
  4. Y Schenk3,
  5. J W G Jacobs4,
  6. J W J Bijlsma4,
  7. R Geenen1,4
  1. 1Department of Clinical and Health Psychology, Utrecht University, Utrecht, The Netherlands
  2. 2Department of Psychology, Wayne State University, Detroit, Michigan, USA
  3. 3Department of Rheumatology, Diakonessenhuis Utrecht, Utrecht, The Netherlands
  4. 4Department of Rheumatology and Clinical Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
  1. Correspondence to Marianne B Kool, Department of Clinical and Health Psychology, Utrecht University, PO Box 80140, 3508 TC Utrecht, The Netherlands; m.b.kool{at}uu.nl

Abstract

Background Patients with rheumatic diseases may face ‘discounting’ (denying and patronising) or ‘lack of understanding’ because of having symptoms without external clinical signs, but instruments to assess such invalidation experiences are lacking.

Objectives To develop and evaluate the Illness Invalidation Inventory (3*I), to compare invalidation experiences of two groups of patients who differ in visual signs and laboratory findings—rheumatoid arthritis (RA) and fibromyalgia—and to examine the association of invalidation with health status.

Methods A questionnaire (eight items with respect to five sources: spouse, family, medical professionals, work environment and social services) was constructed. It was completed by 142 patients with RA and 167 patients with fibromyalgia.

Results Principal axis factoring with oblimin rotation yielded two factors with high internal consistency (α>0.70): ‘discounting’ (five items) and ‘lack of understanding’ (three items). Patients with fibromyalgia experienced significantly more discounting and lack of understanding from their family, medical professionals, colleagues and social services than did patients with RA. Both patient groups experienced more invalidation from social services, colleagues and family than from medical professionals and spouses. More discounting and lack of understanding correlated with poorer mental well-being and social functioning in both patient groups. Discounting correlated with more physical disability and pain in patients with RA.

Conclusions The 3*I is a brief, reliable instrument for assessing patients' perceptions of invalidation from different sources, which differ between patient groups and are associated with health status. Future validation research should clarify the clinical impact of invalidation on treatment adherence and outcome.

https://doi.org/10.1136/ard.2009.123224

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    Symptoms of rheumatic diseases such as pain, fatigue and stiffness are inherently invisible. This invisibility, particularly when accompanied by a lack of physical deformity or laboratory findings that indicate a disease process, can provoke rejection, disbelief or a lack of understanding from the social environment. This experience, which we term invalidation, encompasses the perception of cognitive, affective and behavioural responses of others that are perceived as denying, lecturing, overprotecting, not supporting and not acknowledging with respect to the condition of the patient.1

    In addition to its presumed negative effect on mental well-being,2,–,8 invalidation is hypothesised to negatively influence physical health and social functioning. Firstly, invalidation includes a lack of positive social responses, and social support is thought to both directly promote health and buffer the effect of external stressors on health.9 Secondly, invalidation includes negative social responses and social rejection, which may harm psychological well-being10 and amplify pain,11 probably through neural mechanisms.12 13 Thirdly, to prevent social rejection, patients may hide their illness and its consequences or isolate themselves from others,4 14 which negatively affects their social relationships and functioning,15 and possibly also their health because of low healthcare adherence or because healthcare providers are not fully informed.

    Previously developed instruments specified constructs that are related to social rejection, but did not assess invalidation related to invisible symptoms such as pain and fatigue, and the questionnaires did not include items generated by patients with rheumatic diseases.16,–,18 Therefore important aspects such as dismissing a person's inability to work, disbelieving and admonishing were not included in previous instruments. Also, previous measures did not differentiate among sources of invalidation,19,–,22 whereas a full account of invalidation requires acknowledging both the target and the source. Patients differ with respect to their vulnerability to invalidation, and social sources such as the spouse, family, medical professionals, colleagues and people in social services differ in the extent to which they show validation or invalidation.1 A questionnaire measuring invalidation may give us more insight into the invalidation experienced by patients with rheumatic diseases, will allow further study of this important phenomenon, and will provide information on interventions targeting invalidation.23

    The aim of this study was to construct and evaluate a questionnaire to assess invalidation experiences by the spouse, family, medical professionals, work environment and social services, to compare invalidation of patients with fibromyalgia and rheumatoid arthritis (RA), and to investigate the association of invalidation experiences with health status. Although symptoms in both fibromyalgia and RA are inherently invisible, more invalidation experiences were expected in patients with fibromyalgia than in those with RA because the absence of physical deformity and evidence of pathology in fibromyalgia could amplify invalidation. Also, it was hypothesised that invalidation would be related to worse mental well-being and physical and social functioning and to more severe pain.

    Methods

    Participants

    Participants were 142 patients with RA and 167 patients with fibromyalgia. Inclusion criteria were: being 18 years or older and being diagnosed by a rheumatologist according to established criteria.24 25 Participants with both rheumatic conditions were excluded. Table 1 presents demographic characteristics of the samples. Patient groups did not differ with regard to marital status, level of education, or the percentage working full time, being unemployed, receiving Workmen's Compensation Act or a benefit, or being a housewife. Compared with patients with fibromyalgia, the RA group was older (59 vs 50 years of age; p<0.001), included more men (24% vs 5%; p<0.001), had a longer duration of symptoms (17 vs 14 years; p=0.03) and diagnosis (16 vs 7 years; p<0.001), were less often employed part-time (18% vs 29%; p=0.02), and were more often retired (29% vs 10%; p<0.001).

    View this table:
    Table 1

    Characteristics of patients with rheumatoid arthritis and fibromyalgia

    Procedure

    The study was approved by the medical ethics committee of the University Medical Center Utrecht. Patients with either RA or fibromyalgia at the University Medical Center Utrecht and the Diakonessenhuis Utrecht, The Netherlands, were recruited to participate in a questionnaire study. Spouses were also invited to participate in this questionnaire study to address research questions that are beyond the scope of the current article. Rheumatologists sent an information sheet and consent form to eligible patients. Patients who responded with interest received a questionnaire booklet. Of 425 patients with each condition who received a letter, 160 (38%) with RA and 201 (48%) with fibromyalgia responded. Of those, 142 (89%) with RA and 167 (83%) with fibromyalgia provided complete data and were analysed.

    Pilot work

    In a previous study, the structure of invalidation was found to consist of 15 components.1 The three most characteristic statements of each of these 15 components (in total, 45 items) were selected by the researchers in a consensus meeting for a pilot version of the questionnaire. These 45 items were scored and commented on by 30 patients with rheumatic diseases. Patients scored the items with reference to five sources: spouse, family, medical professionals, work environment and social services. These sources were reported to be important by most patients and were divergent in terms of being close to or distant from patients. Five factor analyses of these pilot data each yielded two factors that applied to all five sources. The criteria used to select items for the final version of the questionnaire were: (1) a maximum of one item for each original cluster, (2) a factor loading above 0.45 after factor analysis, and (3) the items should apply to all five sources. Eight items fulfilled these criteria and were selected for the final questionnaire, the ‘Illness Invalidation Inventory’ (3*I).

    Instruments

    Invalidation was measured with the 3*I, including the same eight items assessing the extent to which people experience invalidation with regard to each of five sources (spouse, family, medical professionals, work environment and social services). The items are shown in table 2. Participants indicated on a 5-point scale (1=never, 2=seldom, 3=sometimes, 4=often, 5=very often) how often during the past year people within each category reacted to them in the described way. A source category that did not apply (eg, because the patient was not employed) could be skipped.

    View this table:
    Table 2

    Factor loadings, eigenvalues, percentage of variance and internal consistency coefficients (Cronbach's α) of the eight items of the 3*I referring to five sources. Principal axis factoring with oblimin rotation for each source in the whole sample of patients with rheumatoid arthritis and fibromyalgia resulted in two factors: discounting (1) and lack of understanding (2)

    To measure health status, the MOS Short-Form General Health Survey (SF-20)26 was used. It consists of 20 items, from which four domains were derived: physical functioning (6 items), social functioning (1 item), mental well-being (5 items) and physical pain (1 item).

    Statistical analysis

    All analyses were performed with SPSS 16.0. Significance level was set at p<0.05. Although the score distributions of some variables were somewhat skewed (highest skewness=1.5), the large sample size allowed parametric statistics. The structure of the 3*I was assessed with principal axis factoring with oblimin rotation (because the factors could be correlated) for each of the five sources, both in the patient groups combined and in the two patient groups separately.

    Pearson correlation coefficients were calculated to examine the association of invalidation scores with demographic characteristics. The difference in invalidation scores between the two patient groups was examined with independent samples t tests. Because age, years since diagnosis, years since the first occurrence of symptoms, and being retired differed between groups and correlated significantly with invalidation, analyses were repeated with analyses of covariance but only controlling for age, because of the high overlap among these covariates. The size of differences was expressed in Cohen's d effect sizes, with values of 0.2, 0.5 and 0.8 reflecting small, moderate and large differences, respectively.27 The frequency of invalidation among patients with fibromyalgia and RA was exemplified by counting the proportion of patients experiencing invalidation ‘never’ or ‘rarely’ (mean invalidation score 1–2.5), ‘sometimes’ (>2.5–3.5) and ‘often’ or ‘very often’ (>3.5–5).

    Differences among the five sources of invalidation were examined with paired-samples t tests on each pair of sources (eg, spouse vs family), using the Bonferroni correction (p<0.005).

    Associations of invalidation scores with mental well-being, physical and social functioning, and pain (health status) were calculated with Pearson's correlation coefficients. Hierarchical regression analyses were used to obtain insight into the correlations that differed between the two patients groups.

    Results

    Factor structure and internal consistency

    Table 2 shows the results of principal axis factoring for the whole sample. The scree plot of eigenvalues, the factor plot and pattern of factor loadings after rotation uniformly suggested two factors. For all sources and both patient groups, the same items loaded on the same two factors.

    Factor 1, labelled ‘discounting’, included denying and patronising responses. Factor 2, labelled ‘lack of understanding’, included supporting and acknowledging responses. Cronbach's α coefficients of the factor discounting were high, from 0.80 (spouse) to 0.94 (social services). Four Cronbach's α coefficients of the factor lack of understanding were high, from 0.79 (work environment) to 0.93 (social services), and one was moderately high, 0.67 (spouse).

    Discounting and lack of understanding scores for the separate sources were determined by calculating the average of the scale items. Scores for items 3, 5 and 8 were first reversed into the direction of lack of understanding. Correlations among the five discounting scores and correlations among the five lack of understanding scores of the different sources were generally moderate (0.23<r<0.52). Correlations between discounting and lack of understanding of the same source were high (spouse, 0.53; family, 0.64; medical professional, 0.62; work, 0.62; social services, 0.70).

    Correlations with patient characteristics

    We examined whether discounting and lack of understanding (10 variables: 2 dimensions, 5 sources) correlated with the 15 variables of table 1. Mostly small (<0.30) correlations were observed with a younger age (–0.36<r<–0.01), a shorter duration of diagnosis (–0.23<r<–0.04), being single (–0.15<r<–0.03), not being widowed (0.14<r<0.18) and not being retired (0.02<r<0.20).

    RA and fibromyalgia

    Table 3 shows that discounting and lack of understanding by the family, medical professionals, work environment and social services were higher in fibromyalgia than RA (p≤0.001). After age had been controlled for, these differences remained significant. The effect sizes of the differences were moderate (0.50<d<0.80) to large (d>0.80). Patients with fibromyalgia experienced discounting ‘sometimes’ and ‘often/very often’ more frequently than patients with RA from their spouse (12% vs 9%), family (36% vs 11%), medical professionals (20% vs 4%), work (43% vs 17%) and social services (69% vs 23%) (figure 1). Lack of understanding scores are shown in the supplementary file online.

    Figure 1
    Figure 1

    Percentage of patients with rheumatoid arthritis (RA) or fibromyalgia (FM) who experience discounting from each of five sources ‘rarely’ or ‘never’, ‘sometimes’, and ‘often’ or ‘very often’ (p values of independent samples t tests).

    View this table:
    Table 3

    Means (M) and SD of discounting and lack of understanding (score ranges 1–5) of patients with rheumatoid arthritis (RA) and patients with fibromyalgia (FM) as experienced from the spouse, family, medical professionals, work environment and social services, and t value, 95% CI of difference, p value and Cohen's d of the group difference

    With respect to the source of invalidation, patients with RA experienced significantly more invalidation from their family than from their spouse (p<0.001), and from social services, the work environment and the family than from medical professionals (p<0.005). Among patients with fibromyalgia, the invalidation scores were significantly higher for social services, the work environment and the family than for medical professionals and the spouse (p<0.005), significantly higher for medical professionals than for the spouse (p<0.005), and significantly higher for the work environment and social services than for the family (p<0.005).

    Correlations between invalidation and health status variables

    Several significant associations of discounting and lack of understanding with health status variables were observed (table 4). Overall, discounting correlated more strongly with health status than did lack of understanding, and these correlations were stronger in patients with RA than in those with fibromyalgia, especially for correlations with physical functioning, pain and mental well-being. Discounting by medical professionals and the work environment correlated most strongly with health status. Discounting and lack of understanding by the spouse and social services hardly correlated with the health status of patients. The correlations remained significant after demographic characteristics had been controlled for using regression analyses. Four correlations between discounting and health status were higher in RA than in fibromyalgia (see supplementary file).

    View this table:
    Table 4

    Correlations of discounting and lack of understanding with physical functioning (PF), pain, mental well-being (MW) and social functioning (SF) in patients with rheumatoid arthritis and in patients with fibromyalgia

    Discussion

    The 40-item (eight items for five sources) 3*I was shown to assess two internally consistent dimensions of invalidation: discounting and lack of understanding. Patients with fibromyalgia perceived more invalidation than patients with RA. The amount of invalidation experienced from social services, colleagues and family was higher than from medical professionals and spouses. More discounting and lack of understanding were associated with worse mental well-being, social functioning and—in the case of discounting in patients with RA—worse physical functioning and pain.

    Discounting represents disbelieving, admonishing, dismissing inability to work, not acknowledging symptom fluctuations, and offering unusable advice. Lack of understanding reflects not recognising, comprehending and emotionally supporting the patient or illness. The inclusion of only eight items may have led to only two dimensions being found. However, the factor analyses in the pilot study with 45 items also yielded only two dimensions, which suggests that large between-subject differences over-ride the within-subject nuances of invalidation found in qualitative analyses.1 We chose not to use double-negative items. The resulting negatively framed items turned out to load on one factor, and the positively framed items loaded on the other factor. It is not clear whether subjects respond to the content, form or both. However, ‘not getting validation’ does not mean the same as ‘getting invalidation’, the consequences of overt rejection versus not being acknowledged appear to be different,10 and discounting correlated more closely with health status than did lack of understanding. This all suggests that it is useful to distinguish these two aspects of invalidation in research and clinical assessment.

    Consistent with qualitative studies,2,–,8 our quantitative study observed that invalidation is a problem for many patients with RA and, as hypothesised, for even more patients with fibromyalgia. That invalidation was so pronounced in fibromyalgia suggests that it might be caused by the lack of knowledge of the syndrome,28 the lack of a medical explanation and medical cure,29 and the low prestige of the illness.30 This may be due to the source of invalidation, but a complementary explanation may be that patients with fibromyalgia more often elicit invalidating responses from their social environment—for example, by spontaneous disclosing of symptoms, by frequently demanding validation, or by showing anger towards the social environment.15 The higher frequency of invalidation in fibromyalgia than RA supports the idea that the invisibility of symptoms and absence of pathological evidence increase invalidation experiences.

    In agreement with previous qualitative studies,18 the amount of invalidation experienced by patients varied among sources. Patients with fibromyalgia reported that their spouse was understanding,2 whereas staff at social services called their symptoms into question4 14 and coworkers expressed lack of understanding and negative reactions.14 31 In contrast with earlier studies,4 6 7 32 a low amount of invalidation from medical professionals was reported by the patients in our study who all had a certified diagnosis. Future research should examine whether invalidation from different sources has a differential effect on patients. Our study suggests that it is important to differentiate among sources of invalidation, and that the work environment and social services are especially common sources of invalidation.

    Research on both social support and social rejection9 10 led us to hypothesise that invalidation would be associated with poor health. We found several small to moderate sized correlations of invalidation with poor mental and social functioning in both patient groups, and with worse physical functioning and more severe pain among patients with RA. Longitudinal research is necessary to examine the sequence of events. Invalidation may amplify pain and worsen health through neurological processes, and it may even activate inflammatory processes through effects on proinflammatory cytokines and glucocorticoid resistance.11 33 34 On the other hand, symptoms of the disease can promote the perception of invalidation.11 Research is necessary to examine potential mechanisms that may explain the association between invalidation and health, such as the visibility, treatability and prognosis of the disease. Most importantly, this study provides a first indication of the potential relevance of discounting and lack of understanding for the health of patients with rheumatic diseases.

    This is the first study to measure the construct ‘invalidation’ in patients with rheumatic diseases. The findings suggest the reliability of the questionnaire and the potential relevance of the construct for health and well-being. A limitation is that patients were recruited from only two hospitals, which may have led to underestimation of invalidation by medical professionals. Moreover, a selection bias in favour of good spouse relationships may have occurred, because spouses were also invited to participate in this study. Future validation research should examine the congruence between invalidation experiences of patients and invalidation as revealed by social sources, the divergence between invalidation and social support, the association between objective assessments of disease severity (such as joint deformity or damage) and validation experiences, and whether invalidation predicts symptom severity, choice of doctors, achievements at and dismissal from work, and therapy choice, adherence and outcome.

    To summarise, the 3*I is suggested to be a reliable and valid brief instrument for assessing patients' perceptions of invalidation from different social sources. Future validation research should clarify the clinical effect of invalidation on symptom severity and therapy adherence and outcome. It is important that people who interact with patients are aware of the invalidation that patients may experience. A challenge for all of us is to ‘educate’ the social environment about the consequences of illnesses and to empower patients to cope with invalidation.

    Acknowledgments

    This study was supported by a grant from the Dutch Arthritis Association. We are very grateful to the participants, and to Paulien Vermaas and Miranda de Jong for their wise advice and commitment in all phases of the study, to Christina van Booma-Frankfort and Regina Huisman of the Diakonessenhuis Utrecht and Leslie Beks of the University Medical Center Utrecht for help with patient recruitment, to Kim van der Bolt, Marieke van den Broek, Kira Freyaldenhoven, Melissa van Oort, Hilde de Snoo and Jorien Tissink for help with data collection and data entry, and to Robert Benschop, Judith Dubas, Roeline Kuijer and Marijn Stok for help with translating the 3*I.

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    Footnotes

    • Funding Dutch Arthritis Association.

    • Competing interests None.

    • Ethics approval This study was conducted with the approval of the medical ethics committee of the University Medical Center Utrecht.

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