A minute of your time: The impact of survey recruitment method and interview location on the value of travel time

Web-based stated preference (SP) surveys are widely used to estimate values of travel time (VTT) for cost–benefit analysis, often with internet panels as the source of recruitment. The recruitment method could potentially bias the results because (1) those who frequently participate in surveys may have a lower opportunity cost of time and (2) people who answer the survey at home or in the office may answer differently because the choice situation is less salient to them. In this paper, we investigate both mechanisms using data from a VTT choice experiment study where respondents were recruited from an internet panel, an alternative email register or on-board/on the station. Within all three groups, some complete the survey while making an actual trip. We find that respondents who were recruited from the internet panel or report being members of a panel have a significantly lower VTT, suggesting that internet panels are less representative in this respect compared to other recruitment methods. We also find that those who answer while traveling have a higher VTT, possibly because the benefits of saving travel time are more salient to them than to those who answer while not traveling

Quality of life and functionality after total hip arthroplasty: a long-term follow-up study

<p>Abstract</p> <p>Background</p> <p>There is a lack of data on the long-term outcome of total hip arthroplasty procedures, as assessed by validated tools.</p> <p>Methods</p> <p>We conducted a follow-up study to evaluate the quality of life and functionality of 250 patients an average of 16 years (range: 11-23 years) after total hip arthroplasty using a validated assessment set including the SF-36 questionnaire, Harris Hip Score, WOMAC score, Functional Comorbidity Index, and a study specific questionnaire. Models of multiple stepwise linear and logistic regression analysis were constructed to evaluate the relationships between several explanatory variables and these functional outcomes.</p> <p>Results</p> <p>The SF-36 physical indexes of these patients compared negatively with the normative values but positively with the results obtained in untreated subjects with severe hip osteoarthritis. Similar results were detected for the Harris Hip Score and WOMAC score. There was a 96% rate of post-surgical satisfaction. Hip functionality and comorbidities were the most important determinants of physical measures on the SF-36.</p> <p>Conclusions</p> <p>Patients who had undergone total hip arthroplasty have impaired long-term self-reported physical quality of life and hip functionality but they still perform physically better than untreated patients with advanced hip osteoarthritis. However, the level of post-surgical satisfaction is high.</p

18 years of results with cemented primary hip prostheses in the Norwegian Arthroplasty Register: Concerns about some newer implants

Background and purpose Few studies have compared the long-term survival of cemented primary total hip arthroplasties (THAs), and several prostheses have been used without adequate knowledge of their endurance. We studied long-term outcome based on data in the Norwegian Arthroplasty Register

Women in Charnley class C fail to improve in mobility to a higher degree after total hip replacement

BACKGROUND: The Charnley comorbidity classification organizes patients into 3 classes: (A) 1 hip involved, (B) 2 hips involved, and (C) other severe comorbidities. Although this simple classification is a known predictor of health-related quality of life (HRQoL) after total hip replacement (THR), interactions between Charnley class, sex, and age have not been investigated and there is uncertainty regarding whether A and B should be grouped together. METHODS: We selected a nationwide cohort of patients from the Swedish Hip Arthroplasty Register operated with THR due to primary osteoarthritis between 2008 and 2010. For estimation of HRQoL, we used the generic health outcome questionnaire EQ-5D of the EuroQol group. This consists of 2 parts: the EQ-5D index and the EQ VAS estimates. We modeled the EQ-5D index and the EQ VAS against the self-administered Charnley classification. Confounding was controlled for using preoperative HRQoL values, pain, and previous contralateral hip surgery. RESULTS: We found that women in class C had a poorer EQ-5D outcome than men. This effect was mostly due to the fact that women failed to improve in the mobility dimension; only 40% improved, while about 50% of men improved. Age did not interact with Charnley class. We also found that the classification performed best without splitting or aggregating classes. INTERPRETATION: Our results suggests that the self-administered Charnley classification should be used in its full capacity and that it may be interesting to devote special attention to women in Charnley class C