School of Psychology, Faculty of Health and Medical Sciences, The University of Adelaide, South Australia, Australia.
School of Psychology, Faculty of Health and Medical Sciences, The University of Adelaide, South Australia, Australia; GenesisCare Radiation Oncology, Adelaide, South Australia, Australia.
J Psychosom Res. 2020 May;132:109979. doi: 10.1016/j.jpsychores.2020.109979. Epub 2020 Feb 29.
Response expectancies of cancer treatment toxicities are often, but not always, associated with subsequent experiences. A recent meta-analysis indicated that response expectancies, measured using different assessment formats, reveal different effect sizes, potentially explaining mixed outcomes. Utilizing a clinical sample, we compared 5-point assessments and visual analogue scales, as measures of response expectancies for the incidence and severity of subsequent toxicities.
Four weeks pre-radiotherapy, 45 men with prostate cancer rated their response expectancies of the same 18 toxicities on 5-point assessments and visual analogue scales, presented in random order. Descriptors anchored each end of visual analogue scales and every point of 5-point assessments was labelled, including an 'unsure' midpoint. Toxicities were subsequently assessed 2-weeks into radiotherapy on 100-point visual analogue scales.
Across all toxicities, 17.5-62.8% of patients selected 'unsure' on 5-point assessments. No response expectancies were reported on 5-point assessments for 'blood in stools' or 'rectal urgency' yet 54.8%-64.3% of patients indicated response expectancies for these toxicities on visual analogue scales. Visual analogue scales and 5-point scales demonstrated small-to-moderate associations (r = 0.30-0.58) as measures of response expectancy incidence, but mostly large associations when visual analogue scales captured severity (r = 0.43-0.76). Response expectancies measured with visual analogue scales predicted more toxicities to a moderate degree or greater (68.8%) than 5-point assessments (37.5%).
This novel investigation demonstrated an 'unsure' midpoint is often selected, potentially reducing the sensitivity of 5-point assessments. Based on their associations, and outcomes, these assessment formats should be considered independent in response expectancy research of cancer treatment toxicities.
癌症治疗毒性的反应预期通常与随后的经历有关，但并非总是如此。最近的一项荟萃分析表明，使用不同评估格式测量的反应预期会揭示不同的效果大小，这可能解释了混合结果。利用临床样本，我们比较了 5 点评估和视觉模拟量表，作为对随后毒性发生和严重程度的反应预期的测量方法。
在放射治疗前 4 周，45 名前列腺癌男性患者在 5 点评估和视觉模拟量表上随机呈现的 18 种毒性中，对他们的反应预期进行了评估。视觉模拟量表的每一端都有描述符，5 点评估的每个点都有标签，包括一个“不确定”的中点。毒性在放射治疗后 2 周用 100 点视觉模拟量表进行评估。
在所有毒性中，17.5%-62.8%的患者在 5 点评估中选择“不确定”。5 点评估未报告“粪便带血”或“直肠急迫”的反应预期，但 54.8%-64.3%的患者在视觉模拟量表上表示对这些毒性有反应预期。视觉模拟量表和 5 点量表在测量反应预期发生率方面显示出小到中度的关联（r=0.30-0.58），但在测量视觉模拟量表捕捉严重程度时关联较大（r=0.43-0.76）。视觉模拟量表测量的反应预期在中等程度或更大程度上预测了更多的毒性（68.8%），而 5 点评估则预测了 37.5%。
这项新的研究表明，“不确定”中点通常被选中，这可能降低了 5 点评估的敏感性。基于它们的关联和结果，在癌症治疗毒性的反应预期研究中，这些评估格式应被视为独立的。
