Felix Fischer
Biographic Data
| ID | 5492659 |
|---|---|
| NAME | Felix Fischer |
| GIVEN NAMES | Felix |
| FAMILY NAME | Fischer |
| SIGNATURE | FISCHER F |
| AFFILIATIONS | Charité - Universitätsmedizin Berlin |
| ORCID | 0000-0002-9693-6676 |
| VERIFIED | Yes |
| TOTAL WORKS | 21 |
| TOTAL CITATIONS | 2 |
| AUTHOR COUNT | 21 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 2008 |
| LATEST PUBLICATION YEAR | 2026 |
| H-INDEX | 1 |
Optimal impartial correspondences
We study mechanisms that select a subset of a set of agents based on nominations among them. The goal is to maximize the minimum number of nominations received by any selected agent, subject to an impartiality constraint that the selection of a particular agent must be independent of the nominations cast by that agent. For situations where each agent casts at most d nominations, we give a mechanism that selects at most $$d+1$$ d + 1 agents and on…
Reference values for the PROMIS® physical function item bank version 2.0 in the general population
Considering the cultural differences between Western and Asian countries, we recommend establishing country-specific reference values on a global scale
Differential item functioning between English, German, and Spanish PROMIS® physical function ceiling items
Our findings support the universal applicability of PROMIS Physical Function items across general populations in Argentina, Germany, and the U.S. The sensitivity analyses indicate that the identification of DIF items was robust for different data analytic decisions. Multiverse analysis is a promising approach to address lack of clear cutoffs in DIF identification
Using a measurement type-independent metric to compare patterns of determinants between patient-reported versus performance-based physical function in hemodialysis patients
Patient-reported and performance-based assessments were similarly associated with an objective marker of physical impairment in hemodialysis patients. Age and fatigue may result in discrepancies when comparing performance-based and patient-reported scores on the common PF scale. Trial Registration CONVINCE is registered in the Dutch Trial Register (Register ID: NL64750.041.18). The registration can be accessed at: https://onderzoekmetmensen.nl/en…
PROMIS-29 and EORTC QLQ-C30
EORTC QLQ-C30 and PROMIS-29 showed similar scores and satisfactory agreement in conceptional and statistical analysis. This suggests that the underlying conceptualization of health is reasonably close. Hence, the development of score transformation algorithms or calibration of both instruments on common scales could prospectively increase the comparability of clinical and research PRO data collected with either instrument
Measuring PROMIS pain interference in German patients with chronic conditions
The German PROMIS PI item bank proved to be a clinically valid and precise instrument for assessing pain interference in patients with chronic conditions
Measuring individual true change with PROMIS using IRT-based plausible values
Applying Item Response Theory to the OPD Structure Questionnaire
Recent developments in the dimensional assessment of personality functioning have made the implementation of latent measurement models increasingly attractive. In this study, we applied item response theory (IRT) to a well-established personality functioning instrument (the OPD Structure Questionnaire) to identify a unidimensional latent trait and to evaluate the feasibility of computer adaptive testing (CAT). We hypothesized that the use of IRT …
Accuracy of the PHQ-2 Alone and in Combination With the PHQ-9 for Screening to Detect Major Depression
Importance: The Patient Health Questionnaire depression module (PHQ-9) is a 9-item self-administered instrument used for detecting depression and assessing severity of depression. The Patient Health Questionnaire-2 (PHQ-2) consists of the first 2 items of the PHQ-9 (which assess the frequency of depressed mood and anhedonia) and can be used as a first step to identify patients for evaluation with the full PHQ-9. Objective: To estimate PHQ-2 accur…
Scoring Depression on a Common Metric
There are a growing number of item response theory (IRT) studies that calibrate different patient-reported outcome (PRO) measures, such as anxiety, depression, physical function, and pain, on common, instrument-independent metrics. In the case of depression, it has been reported that there are considerable mean score differences when scoring on a common metric from different, previously linked instruments. Ideally, those estimates should be the s…
Measuring fatigue in cancer patients
Illness Perception of Patients with Functional Gastrointestinal Disorders
The management of FGID patients should take into consideration dysfunctional illness perceptions, non-gastrointestinal symptoms, and emotion regulation
Measurement invariance and general population reference values of the PROMIS Profile 29 in the UK, France, and Germany
Course of self-reported symptoms of 342 outpatients receiving medium- versus long-term psychodynamic psychotherapy
BACKGROUND: The course of self-reported symptoms during medium- versus long-term psychodynamic psychotherapy has rarely been documented for outpatient settings. This observational study describes routine practice of ambulatory treatment in Germany and explores self-reported symptoms of a broad patient sample undergoing one (medium-term) versus two years (long-term) of psychodynamic psychotherapy. METHODS: Over four and a half years, longitudinal …
The validation of a computer-adaptive test (CAT) for assessing health-related quality of life in children and adolescents in a clinical sample
Evaluation of Quality Indicators of Integrated Care in a Regional Psychiatry Budget – A Pre-Post Comparison by Secondary Data Analysis
The Regional Psychiatry Budget (RPB), as a special arrangement within the German Federal Hospital Refund Regulation, is based on the capitation principle. A lump sum is allocated to a major inpatient care provider in a large region on a yearly basis. Under this model, the provider is free to offer all forms of treatment and to construct individual models of integrated care that specifically suit the region and the needs of community members. The …
On the validity of measuring change over time in routine clinical assessment
A new computerized adaptive test advancing the measurement of health-related quality of life (HRQoL) in children
Screening for mental disorders in heart failure patients using computer-adaptive tests
Computerized Adaptive Testing—Ready for Ambulatory Monitoring
Background Computerized adaptive tests (CATs) have abundant theoretical advantages over established static instruments, which could improve ambulatory monitoring of patient-reported outcomes (PROs). However, an empirical demonstration of their practical benefits is warranted. Methods We reviewed the literature and evaluated existing data to discuss the potential of CATs for use in ambulatory monitoring outside clinical facilities. Results Compute…
Computing the minimal covering set
Evaluation of Quality Indicators of Integrated Care in a Regional Psychiatry Budget – A Pre-Post Comparison by Secondary Data Analysis
The Regional Psychiatry Budget (RPB), as a special arrangement within the German Federal Hospital Refund Regulation, is based on the capitation principle. A lump sum is allocated to a major inpatient care provider in a large region on a yearly basis. Under this model, the provider is free to offer all forms of treatment and to construct individual models of integrated care that specifically suit the region and the needs of community members. The …
Computing the minimal covering set
Computing the minimal covering set
Computerized Adaptive Testing—Ready for Ambulatory Monitoring
Background Computerized adaptive tests (CATs) have abundant theoretical advantages over established static instruments, which could improve ambulatory monitoring of patient-reported outcomes (PROs). However, an empirical demonstration of their practical benefits is warranted. Methods We reviewed the literature and evaluated existing data to discuss the potential of CATs for use in ambulatory monitoring outside clinical facilities. Results Compute…
Screening for mental disorders in heart failure patients using computer-adaptive tests
A new computerized adaptive test advancing the measurement of health-related quality of life (HRQoL) in children
On the validity of measuring change over time in routine clinical assessment
Course of self-reported symptoms of 342 outpatients receiving medium- versus long-term psychodynamic psychotherapy
BACKGROUND: The course of self-reported symptoms during medium- versus long-term psychodynamic psychotherapy has rarely been documented for outpatient settings. This observational study describes routine practice of ambulatory treatment in Germany and explores self-reported symptoms of a broad patient sample undergoing one (medium-term) versus two years (long-term) of psychodynamic psychotherapy. METHODS: Over four and a half years, longitudinal …
The validation of a computer-adaptive test (CAT) for assessing health-related quality of life in children and adolescents in a clinical sample
Evaluation of Quality Indicators of Integrated Care in a Regional Psychiatry Budget – A Pre-Post Comparison by Secondary Data Analysis
The Regional Psychiatry Budget (RPB), as a special arrangement within the German Federal Hospital Refund Regulation, is based on the capitation principle. A lump sum is allocated to a major inpatient care provider in a large region on a yearly basis. Under this model, the provider is free to offer all forms of treatment and to construct individual models of integrated care that specifically suit the region and the needs of community members. The …
Illness Perception of Patients with Functional Gastrointestinal Disorders
The management of FGID patients should take into consideration dysfunctional illness perceptions, non-gastrointestinal symptoms, and emotion regulation
Measurement invariance and general population reference values of the PROMIS Profile 29 in the UK, France, and Germany
Scoring Depression on a Common Metric
There are a growing number of item response theory (IRT) studies that calibrate different patient-reported outcome (PRO) measures, such as anxiety, depression, physical function, and pain, on common, instrument-independent metrics. In the case of depression, it has been reported that there are considerable mean score differences when scoring on a common metric from different, previously linked instruments. Ideally, those estimates should be the s…
Measuring fatigue in cancer patients
Accuracy of the PHQ-2 Alone and in Combination With the PHQ-9 for Screening to Detect Major Depression
Importance: The Patient Health Questionnaire depression module (PHQ-9) is a 9-item self-administered instrument used for detecting depression and assessing severity of depression. The Patient Health Questionnaire-2 (PHQ-2) consists of the first 2 items of the PHQ-9 (which assess the frequency of depressed mood and anhedonia) and can be used as a first step to identify patients for evaluation with the full PHQ-9. Objective: To estimate PHQ-2 accur…
Applying Item Response Theory to the OPD Structure Questionnaire
Recent developments in the dimensional assessment of personality functioning have made the implementation of latent measurement models increasingly attractive. In this study, we applied item response theory (IRT) to a well-established personality functioning instrument (the OPD Structure Questionnaire) to identify a unidimensional latent trait and to evaluate the feasibility of computer adaptive testing (CAT). We hypothesized that the use of IRT …
Measuring individual true change with PROMIS using IRT-based plausible values
PROMIS-29 and EORTC QLQ-C30
EORTC QLQ-C30 and PROMIS-29 showed similar scores and satisfactory agreement in conceptional and statistical analysis. This suggests that the underlying conceptualization of health is reasonably close. Hence, the development of score transformation algorithms or calibration of both instruments on common scales could prospectively increase the comparability of clinical and research PRO data collected with either instrument
Measuring PROMIS pain interference in German patients with chronic conditions
The German PROMIS PI item bank proved to be a clinically valid and precise instrument for assessing pain interference in patients with chronic conditions
Differential item functioning between English, German, and Spanish PROMIS® physical function ceiling items
Our findings support the universal applicability of PROMIS Physical Function items across general populations in Argentina, Germany, and the U.S. The sensitivity analyses indicate that the identification of DIF items was robust for different data analytic decisions. Multiverse analysis is a promising approach to address lack of clear cutoffs in DIF identification
Using a measurement type-independent metric to compare patterns of determinants between patient-reported versus performance-based physical function in hemodialysis patients
Patient-reported and performance-based assessments were similarly associated with an objective marker of physical impairment in hemodialysis patients. Age and fatigue may result in discrepancies when comparing performance-based and patient-reported scores on the common PF scale. Trial Registration CONVINCE is registered in the Dutch Trial Register (Register ID: NL64750.041.18). The registration can be accessed at: https://onderzoekmetmensen.nl/en…
Reference values for the PROMIS® physical function item bank version 2.0 in the general population
Considering the cultural differences between Western and Asian countries, we recommend establishing country-specific reference values on a global scale
Optimal impartial correspondences
We study mechanisms that select a subset of a set of agents based on nominations among them. The goal is to maximize the minimum number of nominations received by any selected agent, subject to an impartiality constraint that the selection of a particular agent must be independent of the nominations cast by that agent. For situations where each agent casts at most d nominations, we give a mechanism that selects at most $$d+1$$ d + 1 agents and on…
Medicine (15 works) · Psychology (14 works) · Clinical Psychology (10 works) · Psychometrics (10 works) · Public health (9 works) · Quality of Life Research (9 works) · Clinical Psychology (7 works) · Item response theory (7 works) · Mathematics (7 works) · Computerized adaptive testing (6 works)