Sand T, Zwart J A, Helde G, Bovim G
Department of Neurology, Trondheim University Hospital, Norway.
Cephalalgia. 1997 Nov;17(7):748-55. doi: 10.1046/j.1468-2982.1997.1707748.x.
Pain pressure thresholds (PPT) were measured at 13 cephalic points bilaterally in 30 headache patients (10 with tension-type headache, 10 with migraine and 10 with cervicogenic headache) and 10 control subjects on three different days. During the sessions, the subjects reported their pain intensity on the right and left sides of the head on a visual analogue scale (VAS). The variability between days was estimated as a coefficient of repeatability (CR = 2 standard deviations of intraindividual differences). The mean CR across all 13 locations was larger in headache patients (2.0 kg/cm2) than in controls (1.68 kg/cm2). Variability (CR) was larger in headache patients as compared to control subjects for 11 of the 13 points (p = 0.02). Reliability was better in controls (intraclass correlation coefficients (ICC) ranging from 0.55 to 0.85) than in headache patients (ICC ranging from 0.43 to 0.78). A moderate negative association between PPT and pain intensity was demonstrated. The intraindividual PPT difference (PPT on the most painful occasions-PPT on the least painful occasions) was negative at 12 of 13 cephalic points (p = 0.003, across-location mean difference: -0.20 kg/cm2). The PPT differed significantly from one day to the next. A part of this variation was presumably related to the circumstances around the procedure; thresholds were lower when the subjects came directly to algometry without any preceding medical examination at all 13 points (p = 0.0002). These results have implications for the planning of future algometer studies. The sample size that is required in studies of headache patients is greater than that in studies of healthy subjects, especially when patients suffer from pain during the PPT session. Particular attention should be paid to circumstances (e.g. preceding medical investigations) around the algometry procedure in order to reduce variability.
在三天内，对30名头痛患者（10名紧张型头痛患者、10名偏头痛患者和10名颈源性头痛患者）和10名对照受试者双侧13个头面部穴位测量疼痛压力阈值（PPT）。在测量过程中，受试者使用视觉模拟量表（VAS）报告头部左右两侧的疼痛强度。日间变异性通过重复性系数进行估计（CR =个体内差异的2倍标准差）。所有13个测量部位的平均CR在头痛患者中（2.0kg/cm²）高于对照组（1.68kg/cm²）。13个测量点中的11个点，头痛患者的变异性（CR）高于对照受试者（p = 0.02）。对照组的可靠性更好（组内相关系数（ICC）范围为0.55至0.85），高于头痛患者（ICC范围为0.43至0.78）。PPT与疼痛强度之间存在中度负相关。个体内PPT差异（最痛时的PPT - 最不痛时的PPT）在13个头面部穴位中的12个点为负值（p = 0.003，跨部位平均差异：-0.20kg/cm²）。PPT在不同日期之间存在显著差异。这种变化的一部分可能与测量过程周围的环境有关；当受试者在所有13个测量点均未进行任何前期医学检查而直接进行痛觉测量时，阈值较低（p = 0.0002）。这些结果对未来痛觉测量研究的规划具有启示意义。头痛患者研究所需的样本量大于健康受试者研究，尤其是当患者在PPT测量期间遭受疼痛时。应特别注意痛觉测量过程周围的环境（如前期医学检查），以减少变异性。
