- 期刊
使用水平測量儀及紙張厚度校正法測量下肢長度差異之信度和效度－先驅研究
Measuring Leg-Length Discrepancy by the "Iliac Crest Leveling and Paper Thickness Correction" Method: Reliability and Validity-A Pilot Study
摘要
本研究之目的在於評估臨床上使用水平測量儀和紙張厚度校正法（水平儀紙張厚度測量法）來測量長短腳之信度和效度。而實驗設計是評估同－測量者量測多次以及不同測量者量測之信度及效度。實驗方法：模擬組(n=7)在兩下肢長度無明顯差異的受測者身上用木板塊模擬雙腿不等長之情形(5~25mm)；×光組(n=7)受測者以×光片測量兩腳的不等長。這兩個組均會利用水平測量儀來比較兩邊腸骨棘(iliac crest)的高度差，在較短的腳下墊上紙張，利用增減紙張來校正高度，同時紀錄墊高紙張的厚度代表兩腳不等長的差距。用水平儀來作多次測量比較可以得到測量長短腳的信度；比較水平儀測量值和所模擬出來長短腳的差異程度可計算建構效度(construct validity)；同時效度(concurrent validity)則是比較水平儀測量值和站立姿勢下拍攝的X光片上，股骨頭上緣的高度差異程度。結果，施測者組內以及不同測量者組間信度的級內相關係數(Intraclass correlation coefficient, ICC)分別是.93和.95。建構效度和同時效度則分別是．97和．73。水平儀紙張厚度測量法低估了模擬出的長短腳，平均差異為-1.79±2.64mm (p=.02)，與X光組的比較時其低估中為明顯，平均差異為-5.09±4.35mm (p=.02)，均有明顯統計學上的差異。結論：利用水平儀紙張厚度測量法來測量長短腳具有高度的信度和中度的效度。當病人沒有骨盆畸形的病史，同時腸骨棘可以很容易觸摸到時，我們建議利用水平儀來測量長短腳，並利用紙張厚度校正法來加以定量。
並列摘要
Purpose: To determine the reliability and validity of a clinical measurement of leg-length discrepancy (LLD) using the level and paper thickness correction (LPC) method and testing intrarater and interrater reliability and validity. Method: We recruited 7 people with no apparent LDD as a simulation group. We induced a simulated LLD (5-25 mm) in each subject twice. We also recruited an X-ray group (n=7) consisting of patients with LLD measured by radiographs. To measure the LLD of both groups, an examiner used the LPC method, which involved adjusting bilateral height of the top margin of iliac crest via the level and correcting identified differences by adding some sheets of paper. The thickness of the paper correction was measured by dial caliper. Reliability of LLD measurement (n=7) was determined by using the LPC method to measure the LLD, construct validity (n=14) by comparing LPC measurement with the extent of the induced LLD, and concurrent validity (n=7) by the difference in heights of the superior aspect of the femoral heads from standing radiographs. Results: The intraclass correlation coefficients (ICCs) for the intrarater and interrater reliability were .93 and .95, respectively. The ICCs for the construct and concurrent validities were .97 and .73, respectively. The LPC method underestimated the induced LLD by a mean difference ± SD of -1.79±2.64 mm (p=.02) and the radiographic measure by -5.09±4.35 mm (p=.02). Conclusion: We conclude that the LPC technique for measuring LLD is highly reliable and moderately valid. We recommend using this method of measuring and quantifying LLD when there is no history of pelvic deformity and the iliac crests can be readily palpated.