Psychometric validation of an empowerment scale for Spanish-speaking patients with rheumatoid arthritis

Patient empowerment is a social multidimensional construct [1], largely accomplished by individuals themselves. Most empowerment definitions focus on the individual’s capacity to make decisions about their health-related behavior and to have or take control over aspects of their lives that relate to health [2, 3]. Empowerment has been conceived as a health-enhancing process [3, 4], as a measurable health-related psychosocial outcome [2, 5] and even as an aspect of health-related quality of life (HRQoL) [6]. Currently, there is not a universal definition of empowerment and it has been argued that the construct may be context- and population-specific [7]; culture, age and socioeconomic resources influence empowerment level and the degree to which the different social groups can be and wish to be empowered differ [2]. A study performed in 33 developing countries, 21 of them African, demonstrated considerable variation between countries with regard to the relationship between women’s empowerment and their use of maternal health services; the authors highlighted the need to develop locally sensitive and meaningful measures of (women’s) empowerment [8]. In the field of chronic (non-rheumatic) diseases, empowerment facilitates patients’ involvement in their care and has been related to treatment safety and effectiveness [9, 10], to lower dependence on health services [9, 11], to better treatment adherence, and to improvement in specific health outcomes [9, 10].

Rheumatoid arthritis (RA) is a worldwide chronic inflammatory disease that impacts patients’ HRQoL and may result in increased mortality. Early and aggressive treatment with disease modifying anti-rheumatic drugs (DMARDs) improves outcomes [12]. The 2013 European League against Rheumatism (EULAR) treatment-recommendations for RA emphasizes that treatment must be based on a shared decision between the patient and the rheumatologist [12]. In order to have patients form a partnership with their primary physician in optimizing their health-related disease, patients require knowledge about their disease, skills to self-manage their disease and participate in medical decision making, and power [13]; all of them reflect empowerment attributes.

RA patients from Latin American countries present distinctive characteristics; the literature highlights a lower prevalence [14], a younger age at presentation [14, 15], and a higher female:male ratio [14, 15] in this population, compared with Caucasians. In addition, patients from Latin America present individual and situational sources of vulnerability [14–16] that affect compliance with medications and negatively impact outcomes [15, 17]. Two studies assessed empowerment in RA patients and its association with patient-related outcomes. In the first one, performed in the USA, RA patients found an association between enhancing patients’ empowerment (no validated scale was used) and improvement in some 36-item Short Form (SF-36) categories [18]. The second one was performed in Swedish patients with rheumatic diseases (including RA) and showed an association between patients’ empowerment, as assessed according to a scale that was validated in the same study, and better self-reported health [19]. Few additional studies described empowerment-enhancing approaches in RA patients, although no validated scales were used [20–23]. None of these studies had been performed in Latin American populations, which limits the comprehensiveness of the topic.

Assessment of empowerment requires the use of validated tools with appropriate psychometric properties. A recent systematic review detailed 19 measures with varying quality, 6 of them generic and 13 developed for a specific condition [24]. In addition, a Spanish questionnaire to assess empowerment for self-care has been described, although limited to climacteric women [25]. The Swedish Rheumatic Disease Empowerment Scale (SWE-RES-23) is the only questionnaire adapted for rheumatic diseases and was developed in Swedish [19]. The scale, adapted from the Swedish version of a Diabetes Empowerment Scale, showed adequate psychometric properties in Swedish patients with rheumatic diseases; there is no Spanish version. The Spanish version of the Elders Health Empowerment Scale (S-HES) is a generic scale that reflects the attributes of empowerment construct; its psychometric properties were tested in urban senior citizens (men and women) from Rosario, Argentina [26]. The literature highlights important differences between Hispanic and non-Hispanic Whites, particularly in regard to health-related decision making [27], which is conceptually close to empowerment construct. In addition, the S-HES has shown good validity and reliability (in Spanish-speaking people), is easy to apply as the instrument includes 8 items, and is considered simple to understand according to an elementary literacy level [26, 28], which is relevant for Latin American countries. Based on those considerations, we selected the S-HES, adapted the scale as an RA Empowerment Scale for Hispanic patients (RAEH), and perform its psychometric validation. We present herein the results.

The study was conducted in three steps: (1) RAEH adaptation, (2) pilot testing, and (3) psychometric validation.

In the present study, we performed a psychometric validation of the RAEH, which was adapted from a generic scale that assessed health-related empowerment. RAEH psychometric properties were adequate in terms of construct, content and face validity, and reliability, which were evaluated with internal consistency and test–retest, as recommended [30]. In addition, RAEH was also feasible based on users’ evaluation. Importantly, different samples of consecutive RA outpatients were used to perform analysis. We suggest that RAEH can be used to evaluate empowerment in Hispanic RA patients; the scale is simple and suitable for low-literacy patients and its use could be generalized to Spanish-speaking RA patients from other countries. Although ethnic heterogeneity is characteristic of the Latin American population, RA patients from this geographic area present distinctive characteristics when compared to white populations from the United States and Europe [35].

The RAEH showed adequate internal consistency reliability; Cronbach’s α coefficient for the total scale and the eight empowerment dimensions were good, with α value of 0.86 [33]. The test–retest reliability assessed in 50 patients by the same researcher showed an ICC of 0.79, indicating good reliability [34], with 95% CI of 0.62–0.88. The construct validity was demonstrated by KMO sampling and Barlett’s test of sphericity, both confirming the adequacy of the sample size for conducting factor analysis [33], and a single factor structure was extracted, accounting for 52% of the variance. Face and content validity were examined by patients, and a multidisciplinary committee of health care providers involved in RA management. Patients (RAEH face validity) agreed that items were a valid measure of the corresponding dimension and that items were clear; additional patients confirmed RAEH feasibility. Patients involvement may be particularly relevant as one would expect the indicators of empowerment to be defined by the patients themselves, rather than (or in addition to) by health care professionals. Finally, the RAEH (total score) did not show neither floor nor ceiling effect, which had been defined when more than 15% of the patients achieved the lowest or highest score, respectively [30]. Both, floor and ceiling effects can reduce the possibility of detecting change over time.

This is the first scale validated in the Hispanic population that measures empowerment in patients with RA. There is only one additional scale, the SWE-RES-23, which assessed empowerment in patients with rheumatic diseases [19]. The scale was developed in Swedish and psychometric properties were evaluated in a population primarily represented by middle-aged females; in addition, although patients with different rheumatic diagnosis were included, 74% of them were classified with inflammatory joint diseases, which include RA diagnosis. The RAEH and the SWE-RES-23 showed similar psychometric properties in terms of construct validity, internal consistency and reliability although stability reliability was not tested in the SWE-RES-23, meanwhile the RAEH showed good ICC. Regarding RAEH ceiling effects, it should be mentioned there were ceiling effects in all the individual’s dimensions, which indicates that patients start with higher empowerment skills than the average and may lack room for improvement [30]. Arvidsson et al. also found ceiling effects in two subscales of the SWE-RES-23 and the total score [19], as did Serrani in six out of eight subscales of the S-HES [25] (see Additional file 3).

The median RAEH score for our target population was 34, which confirms that our patients showed an empowerment level above medium values, as has been found in other studies [19, 25]. The average of the empowerment measurement cannot be compared between the RAEH and the SEW-RES-23, because they had different number of reagents and dimensions. Nonetheless, total RAEH mean value (4.2 ± 0.57) was superior to that from either the SWE-RES-23 (vs. 3.53 ± 0.57, p = 0.001) or the S-HES (vs. 3.51 ± 0.73, p = 0.001). Our higher scale mean value may be considered unexpectedly high for a population with limited literacy, but could be explained by the long-term RA duration present in our patients (12 years of disease duration).

Additional studies have tried to measure the level of empowerment in patients with RA; however, empowerment has been measured in a subjective manner. Geller et al. [18] used an empowerment program for 6 months in patients with chronic pain (six of them had RA) and assessed the quality of life, but did not quantitatively measure the level of empowerment. Allam et al. [36] tested the effects of online social support and gamification on health outcomes in 157 RA patients; empowerment levels changed over time, more so in the groups having access to online support or a gamified experience of the website. van der Vaart et al. [37] applied questionnaires and measured use, satisfaction and impact of a web portal, which provided patients with home access to their electronic medical records, in 360 RA patients; only 54% of the respondents (to the questionnaires) had viewed their electronic medical records; among those who had logged in, 44% reported feeling more involved in their treatment, 37% felt they had more knowledge about their treatment, but differences over time were not found on the empowerment-related instruments. Different empowerment-enhancing approaches had been described in RA patients in order to support the patients [20] and promote patient independence [21]. Clinical trials may be considered complex systems, and patients enrolled explained their participation as an experience that substantially improved their control and adaptation by a better understanding of their disease, which may ultimately enhance empowerment [22]. Similarly, alternative models of RA patients’ follow-up, whereby patients initiate appointments themselves, may offer greater self-management of the underlying rheumatic disease [23].

The study has some limitations. First, we did not assess RAEH response to change, neither had indication of minimal important change nor minimal important difference, and without such information, it is impossible to understand if changes in levels of empowerment matters to patients [24]. Second, the RAEH was adapted and validated in a particular population of Hispanic RA outpatients from México and, given cultural differences in Latin America, results present here need to be reproduced in other Spanish-speaking countries. Nonetheless, the RAEH is simple and easy to apply particularly in populations with poor levels of literacy. Third, the RAEH questionnaire assessed empowerment skills at the individual level, but did not account for organizational and community levels that may additionally impact empowerment, particularly in patients with chronic conditions [7]. Finally, the RAEH evaluates empowerment limited to RA; nonetheless, empowerment is a complex construct and it may be necessary to set up a disease-specific context to understand empowerment implications, in terms of outcomes relevant to patients.

In conclusion, RAEH is valid, reliable, and feasible to evaluate empowerment in Spanish-speaking RA patients. Patients from Latin America present unique characteristics and research needs to focus on such populations in order to complete the picture of RA, knowledge of which has been constructed based on studies performed primarily in Caucasians patients. There is (qualitative) evidence in non-rheumatic diseases suggesting that enhancing patient empowerment over their health is highly valued and enables patients to better manage their lives. These, if reproduced in patients with rheumatic diseases, in particular RA, should be conceived as a valuable outcome. The RAEH could be applied in a practical way in studies that use empowerment-enhancing programs in Spanish-speaking RA patients.