The Effect of Interactivity, Tailoring, and Use Intensity on the Effectiveness of an Internet-Based Smoking Cessation Intervention Over a 12-Month Period: Randomized Controlled Trial.

BACKGROUND: eHealth approaches show promising results for smoking cessation (SC). They can improve quit rates, but rigorous research is sparse regarding their effectiveness and the effects of their interactivity, tailoring, and use intensity. OBJECTIVE: We examined the effectiveness of Techniker Krankenkasse Smoking Cessation Coaching (TK-SCC), an internet-based, tailored, and interactive SC intervention. Our hypotheses were as follows: hypothesis 1, in the intervention group (IG; access to TK-SCC), a clinically relevant number of participants will be abstinent at the 12-month follow-up (T3); hypothesis 2, the number of abstinent participants will be significantly greater in the IG than the control group (CG) at T3; and hypothesis 3, in the IG, more intense use of TK-SCC will be positively associated with abstinence. METHODS: Individuals who smoke were randomized into the IG (563/1115, 50.49%) or CG (552/1115, 49.51%), which received a noninteractive, nontailored, and information-only web-based intervention. Data were collected before the intervention, at the postintervention time point (T1), at the 4-month follow-up (T2), and at T3. We tested hypothesis 1 through equivalence tests between the IG's success rate and success rates of comparable effective interventions reported in 2 current meta-analyses. For hypothesis 2, we conducted binary logistic regressions. For hypothesis 3, we assigned the IG participants to 1 of 4 user types and used binary logistic regressions with user types as the independent variable and smoking abstinence as the dependent variable. RESULTS: In the IG, 11.5% (65/563) and 11.9% (67/563) of participants were smoke free at T1 and T3, respectively. These values were statistically equivalent to the effects in the 2 meta-analyses, which reported 9% (z score=0.64, P=.74) and 10.9% (z score=-0.71, P=.24) success rates, respectively. In the CG, 6.2% (34/552) of the participants were smoke free at T1, which increased up to 8.2% (45/552) at T3. The difference between the IG and CG was statistically significant only at T1 (odds ratio [OR] 2.0, 99% CI 1.1 to 3.6; P=.002), whereas the effect was nonsignificant following α error corrections at T3 (OR 1.6, 99% CI 0.9 to 2.7; P=.02). In the IG, constant users of the program became smoke free significantly more often than rare users of the program (T1: OR 15.0, 99% CI 6.1 to 36.9; P<.001; T3: OR 6.5, 99% CI 2.8 to 15.5; P<.001). CONCLUSIONS: TK-SCC is effective for SC. However, its superiority compared with a minimal SC intervention could not be confirmed in the long term. Insufficient implementation of the techniques used and cotreatment bias could explain this outcome. Higher use intensity of TK-SCC was positively related to abstinence. Therefore, additional efforts to motivate users to adhere to intervention use as intended could improve the intervention's effectiveness. TRIAL REGISTRATION: German Clinical Trials Register DRKS00020249, Universal Trial Number U1111-1245-0273; https://drks.de/search/de/trial/DRKS00020249. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1186/s13063-021-05470-8.

Effects of a Web-Based Lifestyle Intervention on Weight Loss and Cardiometabolic Risk Factors in Adults With Overweight and Obesity: Randomized Controlled Clinical Trial.

BACKGROUND: The high proportion of people with overweight and obesity has become a worldwide problem in recent decades, mainly due to health consequences, such as cardiovascular diseases, neoplasia, and type 2 diabetes mellitus. Regarding effective countermeasures, the digitization of health services offers numerous potentials, which, however, have not yet been sufficiently evaluated. Web-based health programs are becoming increasingly interactive and can provide individuals with effective long-term weight management support. OBJECTIVE: The purpose of this randomized controlled clinical trial was to evaluate the effectiveness of an interactive web-based weight loss program on anthropometric, cardiometabolic, and behavioral variables and to compare it with a noninteractive web-based weight loss program. METHODS: The randomized controlled trial included people who were aged between 18 and 65 years (mean 48.92, SD 11.17 years) and had a BMI of 27.5 to 34.9 kg/m2 (mean 30.71, SD 2.13 kg/m2). Participants (n=153) were assigned to either (1) an interactive and fully automated web-based health program (intervention) or (2) a noninteractive web-based health program (control). The intervention program focused on dietary energy density and allowed for dietary documentation with appropriate feedback on energy density and nutrients. The control group only received information on weight loss and energy density, but the website did not contain interactive content. Examinations were performed at baseline (t0), at the end of the 12-week intervention (t1), and at 6 months (t2) and 12 months (t3) thereafter. The primary outcome was body weight. The secondary outcomes were cardiometabolic variables as well as dietary and physical activity behaviors. Robust linear mixed models were used to evaluate the primary and secondary outcomes. RESULTS: The intervention group showed significant improvements in anthropometric variables, such as body weight (P=.004), waist circumference (P=.002), and fat mass (P=.02), compared with the control group over the course of the study. The mean weight loss after the 12-month follow-up was 4.18 kg (4.7%) in the intervention group versus 1.29 kg (1.5%) in the control group compared with the initial weight. The results of the nutritional analysis showed that the energy density concept was significantly better implemented in the intervention group. Significant differences in cardiometabolic variables were not detected between the 2 groups. CONCLUSIONS: The interactive web-based health program was effective in reducing body weight and improving body composition in adults with overweight and obesity. However, these improvements were not associated with relevant changes in cardiometabolic variables, although it should be noted that the study population was predominantly metabolically healthy. TRIAL REGISTRATION: German Clinical Trials Register DRKS00020249; https://drks.de/search/en/trial/DRKS00020249. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.3390/ijerph19031393.

Costs of a structured early detection program for advanced liver fibrosis and cirrhosis: insights on the "plus" of Check-up 35.

BACKGROUND: The implementation of an early detection program for liver cirrhosis in a general population has been discussed for some time. Recently, the effectiveness of a structured screening procedure, called SEAL (Structured Early detection of Asymptomatic Liver cirrhosis), using liver function tests (AST and ALT) and APRI to early detect advanced fibrosis and cirrhosis in participants of the German "Check-up 35" was investigated. METHODS: This study identifies the expected diagnostic costs of SEAL in routine care and their drivers and reports on prevailing CLD etiologies in this check-up population. The analysis is based on theoretical unit costs, as well as on the empirical billing and diagnostic data of SEAL participants. RESULTS: Screening costs are mainly driven by liver biopsies, which are performed in a final step in some patients. Depending on the assumed biopsy rates and the diagnostic procedure, the average diagnostic costs are between EUR 5.99 and 13.74 per Check-up 35 participant and between EUR 1,577.06 and 3,620.52 per patient diagnosed with fibrosis/cirrhosis (F3/F4). The prevailing underlying etiology in 60% of cases is non-alcoholic fatty liver disease. DISCUSSION: A liver screening following the SEAL algorithm could be performed at moderate costs. Screening costs in routine care depend on actual biopsy rates and procedures, attendance rates at liver specialists, and the prevalence of fibrosis in the Check-up 35 population. The test for viral hepatitis newly introduced to Check-up 35 as once-in-a-lifetime part of Check-up 35 is no alternative to SEAL.

Predictors of Adherence to Cancer-Related mHealth Apps in Cancer Patients Undergoing Oncological or Follow-Up Treatment-A Scoping Review.

mHealth interventions in cancer care are being increasingly applied in various settings. Nevertheless, there is a phenomenon wherein individuals show different usage patterns, which could affect the effectiveness of the intervention. In general, it is important to know the predictors of app adherence and usage patterns to improve the design and content (i.e., tailoring). The aim of this scoping review was to provide an overview of predictors of adherence to cancer-related mHealth apps in cancer patients. A systematic literature search was conducted in March 2021 in the electronic databases PubMed, CINAHL, and PsychINFO without limitation in year, focusing on cancer patients undergoing oncological or follow-up treatment using mHealth apps. The initial database search yielded a total of N = 8035 records. After title, abstract, and full-text screening, 10 articles met inclusion criteria. Studies were published between 2013 and 2020. Studies focused on children and adolescents (2/10) as well as adults (8/10). The predictors identified could be categorized into sociodemographic variables, cancer-related factors and others. This study provides an initial insight into relevant predictors of app adherence in cancer patients. However, no clear predictor of increased app adherence was found. Further research of usage patterns is therefore needed so that mHealth interventions can be tailored during development.

Reduction of care-relevant risks to older patients during and after acute hospital care (ReduRisk) - study protocol of a cluster randomized efficacy trial in a stepped wedge design.

BACKGROUND: Older patients are at an increased risk of hospitalization, negatively affecting their health and quality of life. Such patients also experience a lack of physical activity during their inpatient stay, as well as being at increased risk of delirium and inappropriate prescribing. These risk factors can accumulate, promoting a degree of morbidity and the development of cognitive impairment. METHODS: Through the ReduRisk-program, patients at risk of functional impairment, immobility, falls, delirium or re-hospitalization shortly after hospital discharge, will be identified via risk-screening. These patients will receive an individually tailored, multicomponent and risk-adjusted prevention program. The trial will compare the effectiveness of the ReduRisk-program against usual care in a stepped-wedge-design, with quarterly cluster randomization of six university hospital departments into intervention and control groups. 612 older adults aged 70 years or more are being recruited. Patients in the intervention cluster (n = 357) will receive the ReduRisk-program, comprising risk-adjusted delirium management, structured mobility training and digitally supported planning of post-inpatient care, including polypharmacy management. This study will evaluate the impact of the ReduRisk-program on the primary outcomes of activities of daily living and mobility, and the secondary outcomes of delirium, cognition, falls, grip strength, health-related quality of life, potentially inappropriate prescribing, health care costs and re-hospitalizations. Assessments will be conducted at inpatient admission (t0), at discharge (t1) and at six months post-discharge (t2). In the six-month period following discharge, a health-economic evaluation will be carried out based on routine health insurance data (t3). DISCUSSION: Despite the importance of multicomponent, risk-specific approaches to managing older patients, guidelines on their effectiveness are lacking. This trial will seek to provide evidence for the effectiveness of a multicomponent, risk-adjusted prevention program for older patients at risk of functional impairment, immobility, falls, delirium and re-hospitalization. Positive study results would support efforts to improve multicomponent prevention and the management of older patients. TRIAL REGISTRATION: German Clinical Trials Register, DRKS00025594, date of registration: 09/08/2021.

A nationwide registry for recurrent urolithiasis in the upper urinary tract - The RECUR study protocol.

BACKGROUND: Urinary stone disease is a widespread disease with tremendous impact on those affected and on societies around the globe. Nevertheless, clinical and health care research in this area seem to lag far behind cardiovascular diseases or cancer. This may be due to the lack of an immediate deadly threat from the disease and therefore less public and professional interest. However, the patients suffer from recurring, sometimes intense pain and often must be treated in hospital. Long-term morbidity includes doubled rates of chronic kidney disease and arterial hypertension after at least one stone-related event. Observational studies, more specifically, registries and other electronic data sets have been proposed as a means of filling critical gaps in evidence. We propose a nationwide digital and fully automated registry as part of the German Ministry for Education and Research (BMBF) call for the "establishment of model registries". METHODS: RECUR builds on the technical infrastructure of Germany's Medical Informatics Initiative. Local data integration centres (DIC) of participating medical universities will collect pseudonymized and harmonized data from respective hospital information systems. In addition to their clinical data, participants will provide patient reported outcomes using a mobile patient app. Scientific data exploration includes queries and analysis of federated data from DICs of eleven participating sites. All primary patient data will remain at the participating sites at all times. With comprehensive data from this longitudinal registry, we will be able to describe the disease burden, to determine and validate risk factors, and to evaluate treatments. Implementation and operation of the RECUR registry will be funded by the BMBF for five years. Subsequently, the registry is to be continued by the German Society of Urology without significant costs for study personnel. DISCUSSION: The proposed registry will substantially improve the structural and procedural framework for patients with recurrent urolithiasis. This includes advanced diagnostic algorithms and treatment pathways. The registry will help us identify those patients who will most benefit from specific interventions to prevent recurrences. The RECUR study protocol and the registry's technical architecture including full digitalization and automation of almost all registry-associated proceedings can be transferred to future registries. TRIAL REGISTRATION: This study is registered at the German Clinical Trial Register (Deutsches Register Klinischer Studien), DRKS-ID DRKS00026923 , date of registration January, 11th 2022.

Psychometric properties of the German version of the Psychological Consequences of Screening Questionnaire (PCQ) for liver diseases.

Background: This study aimed to translate the negative and positive items of the Psychological Consequences Questionnaire (PCQ) into German, to adapt this version to the context of screening for cirrhosis and fibrosis of the liver, and to test its psychometric properties. Materials and methods: The three subscales (physical, emotional, and social) were translated into German using a forward-backward translation method. Furthermore, we adapted the wording to the context of liver diseases. In sum, the PCQ comprises twelve negative items and ten positive items. We tested the acceptability, distribution properties, internal consistency, scale structure, and the convergent validity using an analysis sample of 443 patients who were screened for cirrhosis or fibrosis of the liver. Results: We found low non-response and non-unique answer rates on the PCQ items in general. However, positive items had higher non-response rates. All items showed strong floor effects. McDonald's Omega was high for both the negative (ω = 0.95) and the positive PCQ scale (ω = 0.90), as well as for the total PCQ scale (ω = 0.86). Confirmatory factor analysis could reproduce the three dimensions that the PCQ intends to measure. However, it suggests not summing up a total PCQ score and instead treat the subscales separately considering a higher order overall construct. Convergent validity with the short form of the Spielberger State-Trait Anxiety Inventory (STAI-Y-6) was acceptable. Conclusion: Overall, our study results report a successful adaptation of the German PCQ with good performance in terms of acceptability, internal consistency, scale structure, and convergent validity. Floor-effects limit the content validity of the PCQ, which needs to be addressed in future research. However, the German version of the PCQ is a useful measurement for both negative and positive screening consequences - even in a non-cancer setting.

Over- and under-prescribing, and their association with functional disability in older patients at risk of further decline in Germany - a cross-sectional survey conducted as part of a randomised comparative effectiveness trial.

BACKGROUND: Older patients at risk of functional decline are frequently affected by polypharmacy. This is associated with a further loss of independence. However, a relationship between functional disability and medications, such as 'Potentially Inappropriate Medications' (PIMs) and 'Potential Prescribing Omissions' (PPOs), as itemised for (de) prescribing in practice-orientated medication lists, has yet to be established. METHODS: As part of a randomised comparative effectiveness trial, LoChro, we conducted a cross-sectional analysis of the association between PIMs and PPOs measured using the 'Screening Tool of Older Persons' Prescription Criteria / Screening Tool To Alert to Right Treatment' (STOPP/START) Version 2, with functional disability assessed using the 'World Health Organization Disability Assessment Schedule 2.0' (WHODAS). Individuals aged 65 and older at risk of loss of independence were recruited from the inpatient and outpatient departments of the local university hospital. Multiple linear regression analysis was used to model the potential prediction of functional disability using the numbers of PIMs and PPOs, adjusted for confounders including multimorbidity. RESULTS: Out of 461 patients, both the number of PIMs and the number of PPOs were significantly associated with an increase in WHODAS-score (Regression coefficients B 2.7 [95% confidence interval: 1.5-3.8] and 1.5 [95% confidence interval: 0.2-2.7], respectively). In WHODAS-score prediction modelling the contribution of the number of PIMs exceeded the one of multimorbidity (standardised coefficients beta: PIM 0.20; multimorbidity 0.13; PPO 0.10), whereas no significant association between the WHODAS-score and the number of medications was seen. 73.5 % (339) of the participants presented with at least one PIM, and 95.2% (439) with at least one PPO. The most common PIMs were proton pump inhibitors and analgesic medication, with frequent PPOs being pneumococcal and influenza vaccinations, as well as osteoporosis prophylaxis. CONCLUSIONS: The results indicate a relationship between inappropriate prescribing, both PIMs and PPOs, and functional disability, in older patients at risk of further decline. Long-term analysis may help clarify whether these patients benefit from interventions to reduce PIMs and PPOs.

[Needs of Children with Oncological Diseases: Psychometric Review of the Survey Instrument "KiWuF-PädOnk" and First Results]. / Bedürfnisse onkologisch erkrankter Kinder: Psychometrische Überprüfung des Erhebungsinstruments "KiWuF-PädOnk" und erste Ergebnisse.

In der vorliegenden Querschnittstudie wurde ein neu konzipierter Bedürfnisfragebogen für 8- bis 13-jährige Krebspatienten psychometrisch überprüft (N=117). Auf der Grundlage einer explorativen Faktorenanalyse wurden 4 Skalen mit insgesamt 19 Items gebildet. Die interne Konsistenz des Fragebogens ist zufriedenstellend. Die Teilnehmenden äußerten ein starkes Bedürfnis nach sozialer Teilhabe, Sicherheit und Kontrollerleben sowie nach Normalität. Der KiWuF-PädOnk liefert Informationen zu Bedürfnissen aus Patientensicht und fördert somit eine individuumszentrierte psychosoziale Versorgung. In the present cross-sectional study, a newly designed needs questionnaire for 8- to 13-year-old cancer patients was psychometrically tested (N=117). Based on an exploratory factor analysis, 4 scales with a total of 19 items were formed. The internal consistency of the questionnaire is satisfactory. Participants expressed a strong need for social participation, safety and experience of control, and normality. The KiWuF-PädOnk provides information on needs from the patient's perspective and thus promotes individual-centered psychosocial care.

FeV1 and BMI influence King's Sarcoidosis Questionnaire score in sarcoidosis patients.

BACKGROUND: Sarcoidosis is granulomatous disease of unknown origin affecting organ function and quality of life. The King's Sarcoidosis Questionnaire (KSQ) serves as a tool to assess quality of life in sarcoidosis patients with general health and organ specific domains. A German translation has been validated in a German cohort. In this study we assessed, whether clinical parameters influence KSQ scores. METHODS: Clinical data (e.g. lung function, organ impairment, serological parameters) for the German validation cohort were extracted from clinical charts and investigated by correlation and linear regression analyses. RESULTS: KSQ subdomain scores were generally lower in patients with respective organ manifestation or on current therapy. LUNG subdomain was significantly predicted by lung functional parameters, however for general health status, only FeV1 exerted significant influence. GHS was not influenced by serological parameters, but was significantly negatively correlated with body mass index (BMI). KSQ provides additional information beyond lung function, clinical or serological parameters in sarcoidosis patients. Notably, high BMI is significantly negatively associated with patients' well-being as measured by KSQ-GHS. CONCLUSION: This observation may direct further studies investigating the effect of obesity on sarcoidosis-related quality of life and strategies to intervene with steroid-sparing therapies and measures of life style modifications. Trial registration This study was registered in the German Clinical Trials Register (reference number DRKS00010072). Registered January 2016.

Effectiveness of an interactive web-based health program for adults: a study protocol for three concurrent controlled-randomized trials (EVA-TK-Coach).

BACKGROUND: A healthy lifestyle can help prevent diseases that impair quality of life and lead to premature death. The Techniker health insurance fund offers a comprehensive online health program to support users in achieving their health goals of Increasing Fitness, Losing and Maintaining Weight, or Smoking Cessation. METHODS: The aim of this study is to test the long-term effectiveness of the web-based TK-HealthCoach with regard to the primary outcomes of increased physical activity, sustainable weight reduction, and smoking abstinence. We are conducting three interconnected, randomized controlled trials (RCT), one for each health goal, within which participants are allocated to an intervention group (interactive online health program) or a control group (non-interactive online health program). The effects of the intervention groups compared to the control groups will be analyzed by multi-level models for change. Participants' data are captured via online questionnaires before the program starts (baseline t0), again when it ends (t1), and later at two follow-up surveys (t2 and t3); the latter 12 months after t1. We are documenting socio-demographic, health-related, and psychological variables as well as usage behavior data of the programs. According to our sample size calculation, we have to enroll 1114 participants in each Losing and Maintaining Weight and Increasing Fitness RCT and 339 participants in the Smoking Cessation RCT. Additionally, 15-20 participants in the interactive smoking-cessation program will be invited to qualitative telephone interviews with the aim to obtain detailed information concerning utilization, compliance, and satisfaction. The online RCTs' inclusion criteria are: adults of each gender regardless of whether they are insured with Techniker health insurance fund. Persons with impairments or pre-existing conditions require a medical assessment as to whether the program is suitable for them. Specific exclusion criteria apply to each program/RCT. DISCUSSION: We assume that study participants will improve their health behavior by using the offered online health programs and that each health goal's intervention group will reveal advantages regarding the outcome variables compared to the control groups. Study enrollment started on January 1, 2020. TRIAL REGISTRATION: German Clinical Trials Register, Universal Trial Number (UTN): U1111-1245-0273 . Registered on 11 December 2019.

Ten-Year Evaluation of the Population-Based Integrated Health Care System "Gesundes Kinzigtal".

BACKGROUND: The population-based integrated health care system called "Gesundes Kinzigtal" (Integrierte Versorgung Gesundes Kinzigtal, IVGK) was initiated more than 10 years ago in the Kinzig River Valley region, which is located in the Black Forest in the German state of Baden-Württemberg. IVGK is intended to optimize health care while maximizing cost-effectiveness. It consists of programs for promoting health and for enabling cooperation among service providers, as well as of a shared-savings contract that has enabled resources to be saved every year. The goal of the present study was to investigate trends in the quality of care provided by IVGK over the past ten years in comparison to conventional care. METHODS: This is a non-randomized observational study with a control-group design (Kinzig River Valley versus 13 structurally comparable control regions), employing data collected by AOK, a large statutory health-insurance provider in Germany, over the period 2006-2015. Quality assessment was conducted with the aid of a set of indicators, developed by the authors, that was based exclusively on claims data. The statistical analysis of the trends in these indicators over time was conducted with preset criteria for the relevance of any observed changes, as well as preset mechanisms of controlling for confounding factors. RESULTS: For 88 of the 101 evaluable indicators, no relevant difference was seen between the trend over time in the region of the intervention and the average trend in the control regions. Relevant differences in favor of the IVGK were observed for six indicators, and negatively divergent trends compared to the controls were observed for seven indicators. In the main summarizing statistical analysis, no positive or negative difference was found between the Kinzig River Valley and the other regions with respect to trends in the health-care indicators over time. CONCLUSION: An evaluation based on 101 indicators derived from health-insurance data did not reveal any improvement of the quality of care by IVGK and the totality of the programs that were implemented under it. However, under the conditions of the shared-savings contract, no relevant diminution in the quality of care was observed over a period of 10 years either, compared with structurally similar control regions without an integrated care model.

[Online Rehab-Need Test (OREST): Effectiveness of an Invitation to Proactive Screening (self-test) for the Need for Medical Rehabilitation Among Individuals Covered by the German Statutory Pension Insurance Agencies in Baden-Württemberg and the Rhine Region]. / Online-Rehabedarfstest (OREST): Wirksamkeit einer Einladung zu einem proaktiven Screening (Selbsttest) auf Bedarf an medizinischen Rehabilitationsmaßnahmen bei Versicherten der Deutschen Rentenversicherung Baden-Württemberg und Rheinland.

PURPOSE: Up to now, there has been a lack of proactive approaches on the part of the rehabilitation providers, while simultaneously a suspected unmet rehabilitation need exists in some groups of insured persons. Therefore, the effectiveness of the invitation to a web-based self-test for rehabilitation needs as a new access route to medical rehabilitation was evaluated. The main question was whether the intervention leads to more approved rehabilitation applications in the follow-up period of 22 months and whether this effect is also apparent after controlling other influencing variables. METHODS: A randomized, controlled study with N=8000 insured persons of two regional statutory pension insurance agencies was conducted to check the effectiveness of the intervention. Insured persons of the intervention group (IG; n=4000) were informed by mail about the web-based self-test and received individual access data for it (user ID and PIN). The control group (CG; n=4000) received no information about the self-test. The primary outcome was the rate of approved rehabilitation applications, the secondary outcome was the application rate regardless of approval. RESULTS: Groups do not differ significantly in terms of primary or secondary outcomes. Even after controlling for other influencing factors, the intervention does not contribute to the prediction of outcomes, but some control variables, such as previous rehabilitation experience, prove to be important predictors for the application. CONCLUSION: The mere offer of a self-test for rehabilitation need by the pension insurance institution has no effect on the application process. Hence a letter from the pension insurance institution as the sole means of access does not appear suitable for increasing the rate of meaningful rehabilitation applications.

Rationale and methods of an observational study to support the design of a nationwide surgical registry: the MIDAS study.

BACKGROUND Surgical registries are becoming increasingly popular. In addition, Swiss legislation requires data on therapeutic outcome quality. The Swiss Association of Surgeons (Schweizerische Gesellschaft Chirurgie, SGC-SCC) has already agreed on a first minimum data set. However, in the long run the scope and content of the registry should be evidence-based and not only accepted by professional stakeholders. The MIDAS study aims at providing such evidence for the example population of patients undergoing emergency or elective hip surgery. Five relevant aspects are considered: (1) choice of instruments for assessing health related quality of life (HRQoL); (2) optimal time-point for assessment; (3) use of proxy assessments; (4) choice of pre-surgery risk factors; and (5) assessment of peri- and postoperative variables. METHODS MIDAS is a longitudinal observational multicentre study. All patients suffering from a femoral neck fracture or from arthritis of the hip joint with an indication for prosthetic joint replacement surgery will be offered participation. The study is based on a combination of routine data from clinical standard practice with specifically documented data to be reported by the treating clinician and data to be collected in cooperation with the patient ­ in particular patient-reported outcome measures (PROMs). The latter include the Health Utility Index Mark 3 (HUI3) and Euro-Qol-5D (EQ-5D) as generic instruments, Hip Disability and Osteoarthritis Outcome Score (HOOS) as a disease specific instrument for the assessment of HRQoL, and two performance-based functional tests. Data will be collected at baseline, during hospitalisation/at discharge and at three routine follow-up visits. All patients will be asked to name a person for assessing proxy-perceived HRQoL. DISCUSSION To the best of our knowledge, this is the first study explicitly addressing questions about the design of a national surgical registry in an empirical manner. The study aims at providing a scientific base for decisions regarding scope and content of a potential national Swiss surgical registry. We designed a pragmatic study to envision data collection in a national registry with the option of specifying isolated research questions of interest. One focus of the study is the use of PROMs, and we hope that our study and their results will inspire also other surgical registries to take this important step forward. Trial registration Registered at the "Deutsches Register Klinischer Studien (DRKS)", the German Clinical Trials Registry, since this registry meets the scope and methodology of the proposed study. Registration no.: DRKS00012991