Abstract
Objective
Reliable and objective outcome measures to facilitate clinical trials of novel treatments for systemic sclerosis (SS c)–related Raynaud's phenomenon (RP ) are badly needed. Laser speckle contrast imaging (LSCI ) and thermography are noninvasive measures of perfusion that have shown excellent potential. This multicenter study was undertaken to determine the reliability and validity of a hand cold challenge protocol using LSCI , standard thermography, and low‐cost cell phone/mobile phone thermography (henceforth referred to as mobile thermography) in patients with SS c‐related RP .
Methods
Patients with RP secondary to SS c were recruited from 6 UK tertiary care centers. The patients underwent cold challenge on 2 consecutive days. Changes in cutaneous blood flow/skin temperature at each visit were imaged simultaneously using LSCI , standard thermography, and mobile thermography. Measurements included area under the curve (AUC ) for reperfusion/rewarming and maximum blood flow rate/skin temperature after rewarming (MAX ). Test–retest reliability was assessed using intraclass correlation coefficients (ICC s). Estimated latent correlations (estimated from multilevel models, taking values between −1 and 1; denoted as rho values) were used to assess the convergent validity of LSCI and thermography.
Results
In total, 159 patients (77% with limited cutaneous SS c) were recruited (84% female, median age 63.3 years). LSCI and standard thermography both had substantial reliability, with ICC s for the reperfusion/rewarming AUC of 0.67 (95% confidence interval [95% CI ] 0.54, 0.76) and 0.68 (95% CI 0.58, 0.80), respectively, and ICC s for the MAX of 0.64 (95% CI 0.52, 0.75) and 0.72 (95% CI 0.64, 0.81), respectively. Very high latent correlations were present for the AUC s of LSCI and thermography (ρ = 0.94; 95% CI 0.87, 1.00) and for the AUC s of standard and mobile thermography (ρ = 0.98; 95% CI 0.94, 1.00).
Conclusion
This is the first multicenter study to examine the reliability and validity of cold challenge using LSCI and thermography in patients with SS c‐related RP . LSCI and thermography both demonstrated good potential as outcome measures. LSCI , standard thermography, and mobile thermography had very high convergent validity.
Reliable and objective outcome measures to facilitate clinical trials of novel treatments for systemic sclerosis (SS c)–related Raynaud's phenomenon (RP ) are badly needed. Laser speckle contrast imaging (LSCI ) and thermography are noninvasive measures of perfusion that have shown excellent potential. This multicenter study was undertaken to determine the reliability and validity of a hand cold challenge protocol using LSCI , standard thermography, and low‐cost cell phone/mobile phone thermography (henceforth referred to as mobile thermography) in patients with SS c‐related RP .
Methods
Patients with RP secondary to SS c were recruited from 6 UK tertiary care centers. The patients underwent cold challenge on 2 consecutive days. Changes in cutaneous blood flow/skin temperature at each visit were imaged simultaneously using LSCI , standard thermography, and mobile thermography. Measurements included area under the curve (AUC ) for reperfusion/rewarming and maximum blood flow rate/skin temperature after rewarming (MAX ). Test–retest reliability was assessed using intraclass correlation coefficients (ICC s). Estimated latent correlations (estimated from multilevel models, taking values between −1 and 1; denoted as rho values) were used to assess the convergent validity of LSCI and thermography.
Results
In total, 159 patients (77% with limited cutaneous SS c) were recruited (84% female, median age 63.3 years). LSCI and standard thermography both had substantial reliability, with ICC s for the reperfusion/rewarming AUC of 0.67 (95% confidence interval [95% CI ] 0.54, 0.76) and 0.68 (95% CI 0.58, 0.80), respectively, and ICC s for the MAX of 0.64 (95% CI 0.52, 0.75) and 0.72 (95% CI 0.64, 0.81), respectively. Very high latent correlations were present for the AUC s of LSCI and thermography (ρ = 0.94; 95% CI 0.87, 1.00) and for the AUC s of standard and mobile thermography (ρ = 0.98; 95% CI 0.94, 1.00).
Conclusion
This is the first multicenter study to examine the reliability and validity of cold challenge using LSCI and thermography in patients with SS c‐related RP . LSCI and thermography both demonstrated good potential as outcome measures. LSCI , standard thermography, and mobile thermography had very high convergent validity.
| Original language | English |
|---|---|
| Pages (from-to) | 903-911 |
| Number of pages | 9 |
| Journal | Arthritis and Rheumatology |
| Volume | 70 |
| Issue number | 6 |
| Early online date | 23 Apr 2018 |
| DOIs | |
| Publication status | Published - Jun 2018 |
| Externally published | Yes |
Bibliographical note
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.Fingerprint
Dive into the research topics of 'A Multicenter Study of the Validity and Reliability of Responses to Hand Cold Challenge as Measured by Laser Speckle Contrast Imaging and Thermography: Outcome Measures for Systemic Sclerosis Related Raynaud's Phenomenon'. Together they form a unique fingerprint.Profiles
-
John Allen
- Centre for Intelligent Healthcare - Professor of Biosensor and Bioinstrumentation
Person: Teaching and Research