Psychometric Properties of the German Version of the Pain Vigilance and Awareness Questionnaire (PVAQ) in Pain-Free Samples and Samples with Acute and Chronic Pain.

PURPOSE: The way individuals attend to pain is known to have a considerable impact on the experience and chronification of pain. One method to assess the habitual "attention to pain" is the Pain Vigilance and Awareness Questionnaire (PVAQ). With the present study, we aimed to test the psychometric properties of the German version of the PVAQ across pain-free samples and across patients with acute and chronic pain. METHOD: Two samples of pain-free individuals (student sample (N = 255)/non-student sample (N = 362)) and two clinical pain samples (acute pain patients (N = 105)/chronic pain patients (N = 36)) were included in this cross-sectional evaluation of the German PVAQ. Factor structure was assessed using exploratory and confirmatory factor analyses. Reliability was assessed using internal consistency (Cronbach's alpha). Construct validity was tested by assessing correlations between PVAQ and theoretically related constructs. RESULTS: Exploratory factor analysis (non-student sample) and confirmatory factor analysis (student sample, acute pain patient sample) suggested that a two-factor solution best fitted our data ("attention to pain," "attention to changes in pain"). Internal consistency ranged from acceptable to good in all four samples. As hypothesized, the PVAQ correlated significantly with theoretically related constructs in all four samples, suggesting good construct validity in pain-free individuals and in pain patients. CONCLUSION: The German PVAQ shows good psychometric properties across samples of pain-free individuals and patients suffering from pain that are comparable to PVAQ versions of other languages. Thus, the German PVAQ seems to be a measure of pain vigilance equally valid as found in other countries.

[Sleep deprivation and pain: a review of the newest literature]. / Schlafentzug und Schmerz : Ein Review der neuesten Literatur.

It has now been established that sleep deprivation or fragmentation causes hyperalgesia which cannot be explained by a general change in somatosensory perception. However, it has not yet been clarified which of the sleep stages are most relevant for this effect. The seemingly paradoxical effects of sleep deprivation on pain-evoked brain potentials on the one hand and the subjective pain report on the other hand suggest complex changes in gating mechanisms. As the effects on pain and affect can be dissociated a common mechanism of action seems unlikely. Data from animal studies suggest that hyperalgesia due to sleep deprivation might be particularly strong under preexisting neuropathic conditions. Together with results from animal research the finding that endogenous pain modulation (CPM) is impaired by sleep deprivation suggests that the serotoninergic system mediates the effect of sleep deprivation on pain perception. However, other neurotransmitters and neuromodulators still have to be considered. The clinically relevant question arises why sleep deprivation induces hyperalgesia more easily in certain individuals than in others and why this effect then has a longer duration?