Quantitative versus qualitative notions of validity: investigating the validity of PSYCHLOPS as a patient outcome measure in trials of insomnia and sleep problems

IntroductionPSYCHLOPS (‘Psychological Outcome Profiles’)is a novel patient-reported outcome measure developed by Ashworth and colleagues that allows clients to evaluate their progress by measuring severity scores for self-defined problems at the start of, during and after therapy. PSYCHLOPS was administered in a study, ‘Resources for Effective Sleep Treatment (REST)’, designed to assess the feasibility of training primary care clinicians (GPs and nurses) to deliver ‘problem focused therapy’ for insomnia to improve sleep outcomes in adults with insomnia. We aimed in this sub-study to assess both qualitative and quantitative notions of validity of PSYCHLOPS in sleep studies.MethodsPSYCHLOPS was administered by a practice nurse to trial participants in two intervention primary care sites (participants offered ‘problem focused therapy’) and two control sites (participants offered sleep hygiene information) as part of a cluster randomized feasibility study. Other predetermined outcome measures including the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Beck Depression Inventory (BDI) and sleep diaries. We investigated qualitative and quantitative markers of validity including content validity (nature of response to items), internal validity (reliability), criterion validity (strength of relationship with a related variable) and construct validity (strength of relationship with an underlying variable). ResultsA qualitative analysis of test content showed a representative sample of the behavior domain expected in relation to sleep problems including sleep, sleep-related problems and underlying psychosocial and physical problems such as anxiety, worry and arthritis. A positive, statistically significant correlation was found between PSYCHLOPS and ISI (Kendall’s tau = 0.47, p<0.001) but not between PSYCHLOPS and PSQI (Kendall’s tau = 0.13, p=0.24) suggesting partial criterion validity with regards to insomnia impact. We also found a positive correlation between PSYCHLOPS and BDI and (Kendall’s tau = 0.47, p<0.001) indicating construct validity.ConclusionPSYCHLOPS demonstrated some aspects of quantitative validity supporting its wider use in this study setting. However, applying qualitative notions of validity uncovered a number of assumptions and response biases that should be acknowledged in future studies using the tool. Qualitative analysis added an additional dimension to the assessment of validity which should be considered in other validation studies.</p

Additional file 2: of Population preference values for health states in relapsed or refractory B-precursor acute lymphoblastic leukemia in the United Kingdom

Survey instrument: time trade-off exercise. (DOCX 58 kb

Relative Efficacy of Granulocyte-Macrophage Colony-Stimulating Factor, Dacarbazine, and Glycoprotein 100 in Metastatic Melanoma: An Indirect Treatment Comparison

<p><strong>Article full text</strong></p> <p><br> The full text of this article can be found <a href="https://link.springer.com/article/10.1007/s12325-016-0464-9"><b>here</b>.</a><br> <br> <strong>Provide enhanced digital features for this article</strong><br> If you are an author of this publication and would like to provide additional enhanced digital features for your article then please contact <u>[email protected]</u>.<br> <br> The journal offers a range of additional features designed to increase visibility and readership. All features will be thoroughly peer reviewed to ensure the content is of the highest scientific standard and all features are marked as ‘peer reviewed’ to ensure readers are aware that the content has been reviewed to the same level as the articles they are being presented alongside. Moreover, all sponsorship and disclosure information is included to provide complete transparency and adherence to good publication practices. This ensures that however the content is reached the reader has a full understanding of its origin. No fees are charged for hosting additional open access content.<br> <br> Other enhanced features include, but are not limited to:<br> • Slide decks<br> • Videos and animations<br> • Audio abstracts<br> • Audio slides<u></u></p

Indirect Treatment Comparison of Talimogene Laherparepvec Compared with Ipilimumab and Vemurafenib for the Treatment of Patients with Metastatic Melanoma

<p><b>Article full text</b></p> <p><br></p> <p>The full text of this article can be found here<b>. </b><a href="https://link.springer.com/article/10.1007/s12325-016-0313-x">https://link.springer.com/article/10.1007/s12325-016-0313-x</a></p><p></p> <p><br></p> <p><b>Provide enhanced content for this article</b></p> <p><br></p> <p>If you are an author of this publication and would like to provide additional enhanced content for your article then please contact <a href="http://www.medengine.com/Redeem/”mailto:[email protected]”"><b>[email protected]</b></a>.</p> <p><br></p> <p>The journal offers a range of additional features designed to increase visibility and readership. All features will be thoroughly peer reviewed to ensure the content is of the highest scientific standard and all features are marked as ‘peer reviewed’ to ensure readers are aware that the content has been reviewed to the same level as the articles they are being presented alongside. Moreover, all sponsorship and disclosure information is included to provide complete transparency and adherence to good publication practices. This ensures that however the content is reached the reader has a full understanding of its origin. No fees are charged for hosting additional open access content.</p> <p><br></p> <p>Other enhanced features include, but are not limited to:</p> <p><br></p> <p>• Slide decks</p> <p>• Videos and animations</p> <p>• Audio abstracts</p> <p>• Audio slides</p

Methane Emissions from the Natural Gas Transmission and Storage System in the United States

The recent growth in production and utilization of natural gas offers potential climate benefits, but those benefits depend on lifecycle emissions of methane, the primary component of natural gas and a potent greenhouse gas. This study estimates methane emissions from the transmission and storage (T&S) sector of the United States natural gas industry using new data collected during 2012, including 2,292 onsite measurements, additional emissions data from 677 facilities and activity data from 922 facilities. The largest emission sources were fugitive emissions from certain compressor-related equipment and “super-emitter” facilities. We estimate total methane emissions from the T&S sector at 1,503 [1,220 to 1,950] Gg/yr (95% confidence interval) compared to the 2012 Environmental Protection Agency’s Greenhouse Gas Inventory (GHGI) estimate of 2,071 [1,680 to 2,690] Gg/yr. While the overlap in confidence intervals indicates that the difference is not statistically significant, this is the result of several significant, but offsetting, factors. Factors which reduce the study estimate include a lower estimated facility count, a shift away from engines toward lower-emitting turbine and electric compressor drivers, and reductions in the usage of gas-driven pneumatic devices. Factors that increase the study estimate relative to the GHGI include updated emission rates in certain emission categories and explicit treatment of skewed emissions at both component and facility levels. For T&S stations that are required to report to the EPA’s Greenhouse Gas Reporting Program (GHGRP), this study estimates total emissions to be 260% [215% to 330%] of the reportable emissions for these stations, primarily due to the inclusion of emission sources that are not reported under the GHGRP rules, updated emission factors, and super-emitter emissions

Methane Emissions from the Natural Gas Transmission and Storage System in the United States

The recent growth in production and utilization of natural gas offers potential climate benefits, but those benefits depend on lifecycle emissions of methane, the primary component of natural gas and a potent greenhouse gas. This study estimates methane emissions from the transmission and storage (T&S) sector of the United States natural gas industry using new data collected during 2012, including 2,292 onsite measurements, additional emissions data from 677 facilities and activity data from 922 facilities. The largest emission sources were fugitive emissions from certain compressor-related equipment and “super-emitter” facilities. We estimate total methane emissions from the T&S sector at 1,503 [1,220 to 1,950] Gg/yr (95% confidence interval) compared to the 2012 Environmental Protection Agency’s Greenhouse Gas Inventory (GHGI) estimate of 2,071 [1,680 to 2,690] Gg/yr. While the overlap in confidence intervals indicates that the difference is not statistically significant, this is the result of several significant, but offsetting, factors. Factors which reduce the study estimate include a lower estimated facility count, a shift away from engines toward lower-emitting turbine and electric compressor drivers, and reductions in the usage of gas-driven pneumatic devices. Factors that increase the study estimate relative to the GHGI include updated emission rates in certain emission categories and explicit treatment of skewed emissions at both component and facility levels. For T&S stations that are required to report to the EPA’s Greenhouse Gas Reporting Program (GHGRP), this study estimates total emissions to be 260% [215% to 330%] of the reportable emissions for these stations, primarily due to the inclusion of emission sources that are not reported under the GHGRP rules, updated emission factors, and super-emitter emissions