Locus of control and pain: Validity of the Form C of the Multidimensional Health Locus of Control scales when used with adolescents

Abstract

The objective of this study was to examine the factor structure, reliability, and validity of the Form C of the Multidimensional Health Locus of Control scales in adolescents. A confirmatory factor analysis indicated that adequate fit of a four-factor model and the internal consistency of the scales were adequate. Criterion validity of the four scales of the Form C of the Multidimensional Health Locus of Control was also supported by significant correlations with measures of pain-related self-efficacy, anxiety, and coping strategies. The results indicate that the four Form C of the Multidimensional Health Locus of Control scale scores are reliable and valid and therefore support their use to assess pain-related locus of control beliefs in adolescents.

Keywords

locus of control Multidimensional Health Locus of Control pain young people

Introduction

Pain, both acute (Stinson et al., 2008) and chronic (King et al., 2011), is a significant problem in young people that can have widespread negative effects on their lives and their families. Pain can interfere significantly in a child’s psychological and physical functioning (Huguet et al., 2009a), seriously diminishing their quality of life (Gold et al., 2009). Pain is known to be a multidimensional and complex phenomenon where psychological factors—particularly pain-related beliefs—play an important role in how young people cope with and adjust to their pain (Miró et al., 2007).

Beliefs of health locus of control (HLOC) reflect the degree to which people believe that their health status is controlled by their own behavior or by environmental factors (Wallston and Wallston, 1982). Studies with samples of adults with chronic pain have demonstrated that HLOC beliefs are a significant predictor of health behaviors and an important predictor of treatment outcomes (Härkäpää et al., 1991; Hudzinski and Levenson, 1985; Keedy et al., 2014). For example, research has shown that adults with headaches who endorse internal locus of control pain-related beliefs are more confident about being capable of doing things despite pain than those who believe that their health status is determined by external factors (French et al., 2000). Similarly, adults with predominantly external locus of control beliefs have been shown to be more likely to report more pain-related anxiety than people who believe that their pain and the extent to which it interferes with their lives depend on their own behavior (Crisson and Keefe, 1988; Shuster et al., 2009). Other studies have also shown that adults with predominantly internal pain locus of control beliefs are more likely to use more adaptive coping strategies than those with external pain locus of control beliefs who are more prone to use maladaptive coping strategies (Gibson and Helme, 2000; Nicholson et al., 2007). Although this research in adults with pain is consistent with the idea that locus of control beliefs play an important role in adjustment to chronic pain, information regarding the importance of these beliefs in adolescents is limited.

One of the most commonly used measures in adults to assess HLOC beliefs is the Multidimensional Health Locus of Control (MHLC) scales developed by Wallston, Wallston, and DeVellis (Wallston, 2005; Wallston et al., 1978). There are two equivalent forms of the measure (A and B) that assess three HLOC domains: Internal, Chance, and Powerful Others. A third form of this measure, the Form C of the Multidimensional Health Locus of Control (MHLC-C) scales, was developed to assess HLOC beliefs related to specific medical problems by replacing the word “condition” in each item with the medical problem of interest (Wallston et al., 1994). It contains the same number of items as the earlier forms, although the Powerful Others scale was divided into two 3-item scales, namely, Doctors and Other People scales.

Forms A and B of the MHLC scales have been used with adolescents to explore general health beliefs (Astrøm and Blay, 2002; Nada-Raja et al., 1994; Ozolins and Stenström, 2003; Stanton et al., 1995), whereas and to our knowledge, the Form C has not yet been validated in this population. Although research on the MHLC-C scales is limited, a number of studies have examined its factor structure in samples of adults. The four-factor solution suggested by the original authors has been supported in adult populations with a number of different conditions (e.g. rheumatic arthritis, HIV, and pain) (De Las Cuevas et al., 2015; Lundgren et al., 2007; Pereira et al., 2011; Ubbiali et al., 2008). However, the findings regarding the factor structure of the MHLC-C scales are not consistent. For example, at least two studies with adults have supported a three-factor solution in samples of adult patients with conditions such as cancer, irritable bowel syndrome, or diabetes (Jomeen and Martin, 2005; Konkolÿ Thege et al., 2014). In addition, Ip and Martin (2006) found in a sample of pregnant women that neither the four- or three-factor solution could be supported. To date and to the best of our knowledge, researchers have not yet evaluated the factor structure and other psychometric properties of the MHLC-C scales in adolescents. Such basic research is needed in order to determine if the MHLC-C scales can be used to test hypothesized associations between HLOC beliefs and adjustment to pain in adolescents.

The principal aim of this study was therefore to evaluate the psychometric properties of the MHLC-C scales in a sample of adolescents when used to examine pain-related locus of control beliefs. Based on the available evidence from adult studies, cited previously, we hypothesized that the items of the MHLC-C scales would fit better into a four-factor solution than in a three-factor solution as the first alternative has been supported by more studies. In addition, we anticipated that the MHLC-C scales would evidence at least an adequate internal consistency, as indicated by Cronbach’s alpha of 0.70 or greater (Cronbach, 1990). We also hypothesized that the scales of the MHLC-C would evidence adequate criterion validity. Specifically, we hypothesized that (1) scores on the Internal scale would be positively correlated with self-efficacy and negatively associated with pain-related anxiety, and that (2) scores on Chance, Doctors, and Other People scales would be negatively associated with self-efficacy scale scores and positively with pain-related anxiety. We also anticipated a positive and significant association between internal locus of control and adaptive coping strategies. Finally, we expected that a positive and significant correlation would emerge between scores of the scales referring to external locus of control (i.e. Chance, Other People, and Doctors scales) with maladaptive coping strategies.

Methods

Participants

Potential participants were adolescents aged 12–18 years attending a public school. Participants were excluded if they (1) had any cognitive impairment as reported by their teachers or (2) were not able to read and understand Catalan, as the questionnaires were written in that language.

Procedures

The study protocol was approved by the principal of the participating school as well and by the Internal Review Board of the Universitat Rovira i Virgili. To recruit the study participants, we first sent a letter to the parents of potential participants describing the study and asking them whether they would provide consent for their children to participate. In total, 453 letters were sent to parents and 381 (84%) agreed for their children to participate in the study. In addition, children were asked to provide assent prior to data collection, and all of the 381 children asked provided this. However, only data from participants who completed all of the MHLC-C items were included in the analyses, and this occurred in 363 cases (95%) of those who provided some data.

After collecting demographic and pain-related data for descriptive purposes, all participants (both those who reported pain in the previous 3 months and those who did not) were requested to respond to the assessment protocol which took them about 20 minutes. Data were collected during school hours and the protocol was self-administered and anonymous.

Translation of the MHLC-C into Catalan

Because the research was performed in a sample of children who lived in Catalonia, we first translated the MHLC-C scales into Catalan using the back-translation procedure described by Miró (1997). That is, two psychologists fluent in English first translated the MHLC-C instructions and items into Catalan. Next, a native professional translator translated the Catalan version back into English. Finally, in the last step, the back-translated version was sent to another native English speaker to ensure if the back-translated version was equivalent to the original. No additional work or further analysis was required as both forms were found to be linguistically equivalent.

Measures

Descriptive measures

Participants were asked to provide information about their sex, age, and grade level. In addition, participants were asked to report if they had experienced any significant pain somewhere in their body within the 3 months preceding the study. If so, they were then asked to indicate the area(s) of the most frequent pain using a pain drawing used in previous studies (Goodman et al., 1997; Huguet and Miró, 2008) and whether any of them had been present for 3 months or more. Their responses to the pain drawing were then coded into the Axis I (pain location) of the International Association for the Study of Pain (IASP) Classification of Chronic Pain (Merskey and Bogduk, 1994).

Pain-related locus of control

Health-related locus of control was assessed using the MHLC-C scales (Wallston et al., 1994). As indicated previously, this measure was designed to assess people’s beliefs about their ability to control health states resulting from a particular health/medical condition, in this case, pain. Thus, for the purposes of this study, the word “condition” in each of the items was replaced by pain (e.g. “If my pain worsens, it is my own behavior which determines how soon I will feel better again”). The MHLC-C scale has 18 items that are distributed into four independent scales: (1) Internal (six items), that is, the extent to which a person believes that internal factors determine his or her health condition; (2) Chance (six items), that is, the extent to which one believes that his or her health is determined by external factors such as luck or fate; (3) Doctors (three items), that is, the extent to which one believes that his or her health is determined by health professionals; and (4) Other People (three items), that is, the extent to which a person believes that his or her health is determined by others. Each item is rated on a 6-point Likert scale ranging from 1 = “Strongly disagree” to 6 = “Strongly agree,” and the score from each scale is obtained by summing the rating of the items (it is not possible to calculate a total MHLC-C score). Higher scores mean higher levels of locus of control beliefs as assessed by each scale.

Pain coping strategies

Coping strategies used when adolescents experience pain were examined using the Catalan version of the Pain Coping Questionnaire for children (PCQ-C) (Huguet et al., 2009b) which has 36 items that are grouped in seven subscales (i.e. Information Seeking-Problem Solving, Seeking Social Support, Positive Self-Statements, Behavioral Distraction, Cognitive Distraction, Externalizing, and Internalizing/Catastrophizing) and three second-order scales (Approach, Problem-Focused Avoidance, and Emotion-Focused Avoidance). Participants were asked to rate how often they use each coping response on a 5-point Likert scale ranging from 1 = “Never” to 5 = “Very often.” Higher scores in each subscale/second-order factor indicate more frequent use of the type of strategies assessed by that scale. The psychometric properties of the Catalan version of the PCQ-C used here have been previously documented in a sample of schoolchildren (Huguet et al., 2009b). The reliability of the three second-order factors in our sample was good (Cronbach’s alphas = 0.89, 0.87, and 0.82).

Pain-related self-efficacy

The 10-item Pain Self-Efficacy Questionnaire (PSEQ) (Nicholas, 2007) was used to examine participants’ confidence in performing activities despite pain. Participants indicate how confident they are in engaging in each activity listed on 6-point scales where 0 = “Not at all confident” and 6 = “Completely confident.” A total self-efficacy score is calculated by summing each item responses (scores range from 0 to 60), with higher scores reflecting stronger self-efficacy beliefs. We used the Catalan version of the PSEQ that has demonstrated adequate psychometric properties when used with adolescents (Castarlenas et al., 2016), and the reliability of the PSEQ in our sample was excellent (Cronbach’s alpha = 0.91).

Pain-related anxiety

The Child Pain Anxiety Symptoms Scale (CPASS) (Pagé et al., 2010) was used to assess pain-related anxiety. Participants are asked to rate the frequency that they have each of 20 pain-related anxiety responses on a 0 = “Never think, act or feel that way” to 5 = “Always think, act, or feel that way” scale. The CPASS can be scored into four subscales (Cognitive, Physiological Anxiety, Fear, and Avoidance-Escape), and a total score (range from 0 to 100) can be also calculated with higher scores reflecting greater levels of pain-related anxiety. For the analyses of this study, we used the total score. The CPASS has shown to provide valid and reliable data for children and adolescents (Pagé et al., 2010). In this study, we used the Catalan version of the CPASS that has demonstrated good psychometric properties when used with adolescents (Sánchez-Rodríguez et al., 2016). The reliability of the total score in our sample was good (Cronbach’s alpha = 0.87).

Data analyses

We first examined the study variables’ distributions by computing skewness and kurtosis in order to ensure that the assumptions of the planned analyses were met. We also determined if the data were adequate to be factor analyzed by computing the Kaiser–Meyer–Olking test statistic (KMO) and Bartlett’s statistic using Factor 8.1 (http://psico.fcep.urv.es/utilitats/factor/). We then conducted a confirmatory factor analysis (CFA) using Mplus version 5.1 (http://www.statmodel.com/) to evaluate the three- and four-factor solutions of the MHLC-C items. We used the maximum likelihood (ML) as a factor extraction method and to consider that a model had at least an acceptable fit, we determined that the comparative fit index (CFI) value should be 0.90 or greater, that the root mean square error of approximation (RMSEA) value should be 0.08 or lower, and that the standardized root mean residual (SRMR) should be less than 0.10 (Schweizer, 2010). The models tested were (1) the original four-factor model proposed by Wallston et al. (1994), which has been supported by a number of studies (De Las Cuevas et al., 2015; Lundgren et al., 2007; Pereira et al., 2011; Ubbiali et al., 2008), and (2) a three-factor model where items from the Doctors and Other People scales are included in the same scale (Jomeen and Martin, 2005; Konkolÿ Thege et al., 2014).

The successive analyses were planned to be conducted with the factor solution that reach an adequate fit according to the CFA results. Internal consistency was assessed by computing Cronbach’s alphas for each of the scales resulting from the CFA. We then computed Pearson correlation coefficients to examine criterion validity of each of the scales of the questionnaire. Specifically, we computed the correlations between the MHLC-C scores and measures of self-efficacy and pain-related anxiety scores. Finally, we examined the associations between measures of HLOC and pain-related coping strategies. Coping strategies have often been considered adaptive (e.g. information seeking, problem solving, and distraction) and maladaptive (e.g. externalization and catastrophizing), according to the effects on the children and adolescents’ adjustment to pain experience (Huguet et al., 2009a; Lynch et al., 2007; Reid et al., 1998; Thastum et al., 2001). For the purposes of this study, we calculated two scores with the subscales included in the PCQ-C, one referring to adaptive pain coping strategies (by averaging the scores of the following PCQ-C’s subscales: Information Seeking-Problem Solving, Seeking Social Support, Positive Self-Statements, Behavioral Distraction, and Cognitive Distraction) and another referring to maladaptive coping strategies (by averaging the scores of the following PCQ’s subscales: Externalizing and Internalizing/Catastrophizing). We then computed the correlations between the MHLC-C Internal scale score and the resulting score from adaptive coping strategies and between each of the MHLC-C scales assessing external locus of control (i.e. Chance, Other People, and Doctors) and the score from maladaptive coping strategies. These last analyses were computed using SPSS 17.0 (IBM, http://www-01.ibm.com/software/analytics/spss/).

Results

Sample description

Participants were 363 adolescents attending a public school in Reus, Catalonia. Mean age of the participants was 14.24 years (standard deviation (SD) = 1.58 years), and 203 (56%) were girls. Most participants (n = 299, 82%) reported that they had experienced pain in the 3 months prior to the assessment, with the “lower limbs” (20%), the “lower back” (11%), and the “head, face, and mouth” (10%) being identified as the most frequent parts of the body where pain was present. In total, 91 of those (30%) reported that they had chronic pain (i.e. that their pain had been present for 3 months or more) (Merskey and Bogduk, 1994).

CFAs

Values of skewness and kurtosis showed that the distributions of the MHLC-C scale items were essentially normal. A KMO of 0.84 and a significant Bartlett’s test of sphericity (χ² = 1741.7, degree of freedom (df) = 153, p < 0.0001) indicated sampling adequacy for the analyses. The CFA results indicated an inadequate fit of the three-factor model (χ² = 407.75, df = 132, p < 0.001, CFI = 0.83, RMSEA = 0.08, SRMR = 0.07), whereas the four-factor model provided the best overall fit according with the criteria above established (χ² = 283.93, df = 129, p < 0.001, CFI = 0.91, RMSEA = 0.06, SRMR = 0.05), with the factor loadings of each item ranging from 0.56 to 0.79 (see Table 1 for a summary of the results of the CFA for the two models). The results regarding the reliability and validity of the MHLC-C scales, described below, are based on the four-factor solution because this solution evidenced the best fit.

Table 1.

Results of the confirmatory factor analysis for the three-factor model and the four-factor model.

Three-factor model		Four-factor model
Goodness-of-fit indices
χ² = 407.75 (df = 132; p < 0.001)		χ² = 383.93 (df = 129; p < 0.001)
CFI = 0.83		CFI = 0.91
RMSEA = 0.08		RMSEA = 0.06
SRMR = 0.07		SRMR = 0.05
Factor loadings
Internal scale		Internal scale
Item 1	0.56	Item 1	0.56
Item 6	0.67	Item 6	0.67
Item 8	0.71	Item 8	0.71
Item 12	0.63	Item 12	0.63
Item 13	0.69	Item 13	0.69
Item 17	0.65	Item 17	0.65
Chance scale		Chance scale
Item 2	0.64	Item 2	0.64
Item 4	0.63	Item 4	0.63
Item 9	0.78	Item 9	0.79
Item 11	0.75	Item 11	0.76
Item 15	0.60	Item 15	0.60
Item 16	0.71	Item 16	0.72
Doctors/Other People scale		Doctors scale
Item 3	0.51	Item 3	0.57
Item 5	0.56	Item 5	0.70
Item 14	0.59	Item 14	0.71
Item 7	0.60	Other People scale
Item 10	0.52	Item 7	0.70
Item 18	0.51	Item 10	0.64
Item 18	0.51	Item 18	0.58

CFI: comparative fit index; RMSEA: root mean square error of approximation; SRMR: standardized root mean residual; df: degree of freedom.

Reliability–internal consistency

Cronbach’s alphas indicated an adequate internal consistency for three of the scales (Internal = 0.72, Chance = 0.75, and Doctors = 0.70) and marginal reliability for one of scales (Other People = 0.69).

Validity

As hypothesized, scores on the MHLC-C Internal scale correlated positively with scores of self-efficacy as measured by the PSEQ (r = 0.52, p < 0.01) and negatively with a measure of pain-related anxiety (r = −0.47, p < 0.01). Moreover, and consistent with the study hypotheses, scores on the Chance, Doctors, and Other People scales were associated negatively with self-efficacy (r = −0.34, r = −0.42, and r = −0.38, respectively; all ps < 0.01) and positively with pain-related anxiety (rs = 0.43 (p < 0.001), 0.31 (p < 0.05), and 0.39 (p < 0.01), respectively) (Table 2). In addition, and also as hypothesized, Internal Locus of Control was associated positively with adaptive coping strategies (r = 0.59, p < 0.01) and the scores on the Chance, Doctors, and Others People scales, assessing external locus of control, were all related positively with maladaptive coping strategies (r = 0.46, r = 0.26, and r = 0.36, respectively; all ps < 0.05).

Table 2.

Criterion validity of the MHLC-C scales.

Measures	Pearson correlation
Internal scale—self-efficacy	r = 0.52**
Internal scale—pain-related anxiety	r = −0.47**
Internal scale—adaptive coping strategies	r = 0.59**
Chance scale—self-efficacy	r = −0.34**
Chance scale—pain-related anxiety	r = 0.43***
Chance scale—maladaptive coping strategies	r = 0.46*
Doctors scale—self-efficacy	r = −0.42**
Doctors scale—pain-related anxiety	r = 0.31*
Doctors scale—maladaptive coping strategies	r = 0.26*
Other People scale—self-efficacy	r = −0.38**
Other People scale—pain-related anxiety	r = 0.39**
Other People scale—maladaptive coping strategies	r = 0.36*

MHLC-C: Form C of the Multidimensional Health Locus of Control.

p < 0.05; **p < 0.01; ***p < 0.001.

Discussion

In this study, we examined the factor structure, reliability, and validity of the MHLC-C scales. Our work provides several important and unique findings about the use of the MHLC-C when used to assess pain-related locus of control beliefs in adolescents.

The results supported a four-factor solution to the items of the MHLC-C scales. This is consistent with the factor model proposed by the authors of the original questionnaire (Wallston et al., 1994), which was subsequently replicated in samples of adults with different medical conditions (De Las Cuevas et al., 2015; Lundgren et al., 2007; Pereira et al., 2011; Ubbiali et al., 2008). The validity of the MHLC-C scale scores was supported by moderate and significant correlations with the scores on pain-related anxiety, self-efficacy, and coping measures. Specifically, and as hypothesized, adolescents who believed that the control of their pain depends on internal factors showed higher levels of self-efficacy and lower levels of pain-related anxiety. Also, according to the study hypotheses, adolescents who believed that their pain is controlled by external factors showed lower levels of self-efficacy and higher levels of pain-related anxiety. In addition, pain coping strategies considered to be adaptive were associated with an internal locus of control, whereas those thought to be maladaptive were associated with an external locus of control.

The findings have important clinical implications as pain beliefs and attitudes have been suggested to be important factors in the maintenance of pain-related problems in young people (Miró et al., 2007). Available research suggests that HLOC beliefs can influence health behavior and thus can have an impact on what people do (or not do) to improve their health status (Thompson et al., 2016). For example, Farin et al. (2013) found external locus of control to be a risk factor for the improvement in a sample of adults with chronic low back pain who attended to a rehabilitation program. Other studies have also highlighted the locus of control beliefs as important factors that influence patient’s adherence to pain treatment protocols (Keedy et al., 2014; Taddeo et al., 2008). Adolescents with a predominant internal locus of control may think that something can be done to improve their pain problems, and they can be more motivated to follow recommendations from a health professional. A very different situation would be that of an adolescent who believes that his or her pain status and recovery depends on chance; believing that he or she can do nothing to help ease their pain, it is unlikely that he or she would be motivated to adhere to what the health professional suggests for him or her to do. With the availability of a measure of HLOC beliefs that has been shown to provide valid ratings in adolescents, researchers can now examine the role of these beliefs in adjustment to chronic pain in this population, including the potential modifiability of these beliefs with treatment and the impact of changes in these beliefs on subsequent function and quality of life.

The study has a number of limitations that should be considered when interpreting the results. The major limitation is that participants are from a convenience sample of generally healthy adolescents, many of whom did not have chronic pain. An important next step is to replicate these findings in other samples of adolescents with chronic pain to evaluate the generalizability of the current results to populations of youths with various chronic pain conditions. Such research will be useful to continue increasing our knowledge about the role of pain locus of control beliefs in the maintenance of pain problems in youth. Second, because of the use of a cross-sectional design, we were unable to evaluate the test–retest stability of the MHLC-C scales, or their responsiveness to treatment. Further research to evaluate these additional psychometric properties in samples of adolescents would be useful. Finally, because of the limited sample size, we were not able to evaluate how locus of control beliefs might vary as a function of age and whether age moderates the association between locus of control beliefs and various function domains. “Adolescents” comprise a large age range (i.e. 12–18 years) during which conceptions about pain management and attributions might evidence important changes. Research to more closely examine these potential changes is needed.

Despite the study limitations, our study supports the reliability and validity of the MHLC-C scales when used to assess pain locus of control beliefs in adolescents. Furthermore, the findings support the original four-factor structure of the questionnaire. Its widespread use in adults, when considered in light of the data supporting its psychometric properties here, makes the MHLC-C scales a good choice for researchers who wish to evaluate the role that HLOC beliefs play in adjustment to pain in adolescents.

Footnotes

Acknowledgements

The authors would like to thank the participating school for their interest and collaboration in the study.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was partly funded by Obra Social de CaixaBank, the Spanish Ministry of Science (grant nos PSI2012-32471 and PSI2015-70966-P), the European Regional Development Fund (ERDF), and Universitat Rovira i Virgili (PFR program). E.C.’s work is supported by the Spanish Ministry of Economy and Competitiveness (grant no. PSI2014-60180-JIN). J.M.’s work is supported by the Institució Catalana de Recerca i Estudis Avançats (ICREA-Acadèmia) and Fundación Grünenthal. M.R.’s salary and travel support was funded by The Earl Russell Chair in Pain Medicine, Western University, London, Ontario, and by a bequest from the estate of Mrs Beryl Ivey to Dr Warren R. Nielson.

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