McGinnis Elizabeth, Brown Sarah, Collier Howard, Faulks Phil, Gilberts Rachael, Greenwood Clare, Henderson Valerie, Muir Delia, Nelson Andrea, Nixon Jane, Smith Isabelle, Stubbs Nikki, Walker Kay, Wilson Lyn, Coleman Susanne
Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, University of Leeds, Leeds, LS2 9JT, UK.
Leeds Teaching Hospitals NHS Trust, Leeds, UK.
Trials. 2017 Mar 20;18(1):132. doi: 10.1186/s13063-017-1851-5.
PRESSURE 2 is a randomised evaluation of the clinical and cost effectiveness of two types of pressure relieving mattress for the prevention of pressure ulcers. The primary endpoint is the time to development of a Category ≥2 pressure ulcer. The current 'gold standard' for the identification of a Category ≥2 pressure ulcer is expert clinical assessment. Due to the appearance of the bed, it is not possible to achieve blinding of the endpoint. This therefore poses a risk to the internal validity of the study. A possible approach is to use photographs of skin sites, with central blinded review. However, there are practical and scientific concerns including whether patients would agree to photographs; the burden of data collection; the quality of photographs; the completeness of data; and how the use of photographs compares with the current 'gold standard'. This validation sub-study aims to assess and quantify potential bias in the reporting of the trial endpoint.
METHODS/DESIGN: Patients will be specifically asked to consent to photographs being taken of their skin sites. Photographs will be taken at first observation or when patients develop a new Category ≥2 pressure ulcer (to assess over-reporting). A 10% random sample of patients will be identified for additional photographs of two skin sites (one torso and one limb) with and without a pressure ulcer (if present) by an independent assessor (to assess the potential for under-reporting). Staff will be trained to take photographs using a standardised camera and photographic technique. A 'grey scale' will be included in the photo to correct white balance. Photographs will be securely transferred for central review. Photographs will have white balance corrected, and the computer monitor will be calibrated prior to review. Analysis will include assessment of under- and over-reporting, acceptability of photography to patients, secure transfer of data, quality of and confidence in blinded photograph review and sensitivity analysis using photograph assessment of primary outcome.
This study will use photographs to contribute to the primary outcome of the trial. It will inform our understanding of the acceptability of photography for prevention trials and the possibility of other uses of photographic data in clinical work and research.
ISRCTN, ISRCTN01151335 . Registered on 14 May 2013.
“压力2”研究是一项关于两种减压床垫预防压疮的临床及成本效益的随机评估。主要终点是出现≥2期压疮的时间。目前识别≥2期压疮的“金标准”是专家临床评估。由于病床外观的原因，无法实现终点的盲法判定。因此，这对研究的内部效度构成风险。一种可能的方法是使用皮肤部位的照片，并进行中心盲法评审。然而，存在实际和科学方面的问题，包括患者是否会同意拍照；数据收集的负担；照片质量；数据完整性；以及使用照片与当前“金标准”相比的情况。这项验证性子研究旨在评估和量化试验终点报告中的潜在偏倚。
方法/设计：将专门询问患者是否同意拍摄其皮肤部位的照片。在首次观察时或患者出现新的≥2期压疮时拍照（以评估报告过度的情况）。将抽取10%的患者随机样本，由独立评估人员对两个皮肤部位（一个躯干部位和一个肢体部位）在有和没有压疮（如果有）的情况下拍摄额外照片（以评估报告不足的可能性）。工作人员将接受使用标准化相机和摄影技术拍照的培训。照片中将包含一个“灰度标度”以校正白平衡。照片将被安全传输以供中心评审。在评审前，照片将进行白平衡校正，计算机显示器将进行校准。分析将包括评估报告不足和报告过度的情况、患者对拍照的接受程度、数据的安全传输、盲法照片评审的质量和可信度，以及使用照片评估主要结局的敏感性分析。
本研究将使用照片来辅助试验的主要结局。它将使我们了解拍照在预防试验中的可接受性，以及在临床工作和研究中照片数据其他用途的可能性。
国际标准随机对照试验编号，ISRCTN01151335。于2013年5月14日注册。
