Psychological Wellbeing in Chronic Fatigue Syndrome

a brief 12-item scale, with six items corresponding to positive emotions and six items corresponding to negative emotions. Each item is scored on a scale ranging from 1 to 5, where 1 represents "very rarely or never" and 5 represents "very often or always." The positive and negative scales are scored separately and each range from 6 to 30. The two scores can also be combined as a scale of balanced affect. Internal consistency is good (ranging from 0.81-0.89 across the scales), as is temporal stability (0.62-0.68). The SPANE has performed well in terms of convergent validity with other measures of emotion, well-being, happiness, and life satisfaction.

A brief 10-item questionnaire designed to measure two dimensions of meaning in life: (1) Presence of Meaning (the subjective sense that one's life is meaningful), and (2) Search for Meaning (drive and orientation toward finding meaning in one's life). Respondents answer each item on a 7-point Likert-type scale ranging from 1 (Absolutely True) to 7 (Absolutely Untrue). In non-clinical populations both subscales have demonstrated good internal consistency, with cronbach's alphas ranging from 0.86-0.88. In terms of convergent validity, the Presence of Meaning subscale has been found to correlate positively with life satisfaction, positive emotions, extraversion and agreeableness. It has also been found to correlate negative with depression, negative emotions and neuroticism. The Search for Meaning subscale in contrast has been found to correlate positively with neuroticism, depression and several negative emotions.

A 20-item self-report instrument consisting of five scales: General Fatigue, Physical Fatigue, Reduced Activity, Reduced Motivation, and Mental Fatigue. Each scale contains four items rated on a scale of zero to 5 with the scale score of zero having the anchor of entirely true and the scale score of 5 having the anchor of no, not true. In a CFS sample all subscales have demonstrated good internal consistency (general fatigue = 0.89; physical fatigue =0.82, mental fatigue= 0.92; reduced activity= 0.90; reduced motivation= 0.77).

Assesses subjective perception of pain based on a 10-cm line (0-10, no pain to pain as bad as it could be). It is a unidimensional measure of pain intensity, which has been widely used in diverse adult populations, including those with rheumatic diseases. The respondent is asked to place a line perpendicular to the VAS line at the point that represents their pain intensity. A higher score indicates greater pain intensity. Based on the distribution of pain VAS scores in postsurgical patients (knee replacement, hysterectomy, or laparoscopic myomectomy) who described their postoperative pain intensity as none, mild, moderate, or severe, the following cut points on the pain VAS have been recommended: no pain (0 - 4 mm), mild pain (5- 44 mm), moderate pain (45-74 mm), and severe pain (75-100 mm). It takes less than 1 minute to complete (Hawker, Mian, Kendzerska \& French, 2011).

A 14-item measures anxiety and depression in people with physical health problems, excluding items related to somatic symptoms that are higher in these populations. It is widely used and has demonstrated good reliability and validity. A score of above 10 on either subscale is considered clinically significant.