Study design and population
The present study was a follow-up study with a pre–post study design of Norwegian patients with psoriasis, age 20 years and older, who were remitted to a climate therapy programme for 3 weeks at the Canary Islands located in the Atlantic Ocean at 28°N, 16°W. The design included three measurements during a period of 4 months. Patients were recruited into the study at the time they were offered climate therapy. Patients answered a questionnaire just before arriving for (baseline) and just before departing after the 3 weeks of therapy (follow-up 1), and again 3 months later (follow-up 2). The study period lasted from late April 2009 to early January 2010. During this time, 343 psoriasis patients were offered climate therapy; 89 declined to participate (reasons not given), giving a total sample of 254 psoriasis patients. For this paper, data were available for 252 (baseline), 248 (follow-up 1), and 205 (follow-up 2) respondents.
Approval of the study was obtained from the Norwegian Social Science Data Service and the Regional Committee for Medical Research Ethics for Southern Norway, number 6.2009.440. Participants were coded and analysis was performed anonymously. Procedures were in accordance with the Helsinki Declaration of 1975 as revised in 1983.
Patient education in the context of climate therapy
The programme comprised both patient education and sun treatment. A Nordic medical team (dermatologist, nurses, and physiotherapist) monitored the patients. Patients received both individual and group-based education, guidance, and daily training. The teaching programme included information and discussions about psoriasis pathogenesis, manifestations, comorbidity, quality of life, and treatment options. The importance of lifestyle choices was stressed with a special focus on physical activity and healthy eating. Discussions in smaller groups focused on finding ways to manage psoriasis in daily life.
In addition patients received on average 80 hours of sun therapy during their stay. The sun exposure was scheduled individually with respect to skin type and UV index. They were encouraged to bathe frequently in salt water and to use moisturizing creams.
Socio-demographic and clinical variables
Socio-demographic variables such as age, sex, social and marital status, employment status, and educational level were assessed. The following clinical variables were assessed and analysed: years with psoriasis, Psoriasis Area and Severity Index (PASI), comorbidity, and previous climate therapy.
Sense of coherence
The Sense of Coherence Questionnaire (SOC-13) was developed by Antonovsky (Antonovsky 1987). This questionnaire is based on self-report and has been tested for validity and reliability in several studies (Antonovsky 1993;Erikson & Lindstrøm 2005;Erikson & Lindstrøm 2006;Feldt et al. 2007;Hittner 2007). In a systematic review it is concluded that the SOC scale seems to be a reliable, valid and cross-culturally applicable instrument measuring how people manage stress and stay well (Erikson & Lindstrøm 2005). SOC-13 comprises 13 items related to comprehensibility (five items), manageability (four items), and meaning (four items). The total score ranges from 13 to 91, with higher scores indicating a stronger SOC. Responses to all items are scored on a seven-point, Likert-type scale. Missing substitution was performed for individuals who answered at least half of the questions for each component. The Cronbach Alpha (α) was 0.829, Intra Class coefficient (ICC) = 0.829 (95% CI = 0.795, 0.859) in the present study.
Positive and active engagement in life
The positive and active engagement subscale from the Health Education Impact Questionnaire (heiQ) was used to assess positive and active engagement in life. The subscale comprises five items and is scored using a four-point Likert-type scale from “strongly disagree” to “strongly agree” with higher scores indicating stronger positive and active engagement in life. This construct assesses motivation to be active in health education programmes by engaging or re-engaging in life-fulfilling activities as a result of programme participation. Items in this scale aim to measure the individual’s actions to convert intention into positive outcomes, which imply a change of life activities (Osborne et al. 2007). The HeiQ has high construct validity and is a reliable measure of a broad range of patient education programme benefits (Osborne et al. 2007). The Cronbach α for the positive and active engagement subscale used in the present study was 0.733, ICC = 0.733 (95% CI = 0.677, 0.782).
The Revised Illness Perception Questionnaire was used to measure illness perception (Moss-Morris et al. 2002). The questionnaire comprises the following seven components of illness representation: timeline (acute/chronic, six items), consequences (six items), personal control (six items), treatment control (five items), illness coherence (five items), timeline cyclical (four items), and emotional representations (six items). The responses are rated on a five-point Likert scale from “strongly disagree” to “strongly agree”. The Cronbach α for illness coherence, emotional representations and consequences in the present study was 0.870, ICC = 0.870 (95% CI = 0.842, 0.894), 0.856, ICC = 0.856 (95% CI = 0.826, 0.883) and 0.771, ICC = 0.771 (95% CI = 0.723, 0.813), respectively.
The data were analysed using SPSS (version 19.0). Bivariate correlation analyses (Pearson’s r) were used to identify associations between SOC and socio-demographic and clinical variables, and between SOC and illness perception and positive and active engagement in life. Paired t tests were used to evaluate the changes in SOC, positive and active engagement in life and illness perceptions from the baseline to follow-up. To investigate the ability of illness perceptions and positive and active engagement in life (both baseline and change) to predict the change in SOC from the baseline to follow-up 1, we used multiple linear regression analysis with the following eligible independent variables after controlling for SOC at the baseline and the socio-demographic and clinical variables: positive and active engagement in life, the illness perceptions of consequences, coherence and emotional representations, respectively. A 5% level of significance was used to include candidate independents.