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Ingrid Mühlhauser

Publications and source records attributed to Ingrid Mühlhauser.

17 recordsLinked to original sources
PubMed2006

[Surrogate end point fallacies -- the urge for randomized trials with clinical endpoints].

Evidence increases that reliance on surrogate endpoints may be detrimental. This is particularly relevant for preventive medicine. Most impressive examples are hormone replacement therapy, vitamin therapy, and drug treatment of cardiovascular risk factors. Only a few of the oral antidiabetic agents have been studied in randomised trials using clinically relevant outcome measures. Most of these drugs or drug combinations turned out to be more dangerous than beneficial. They increased morbidity and mortality despite their blood glucose lowering effects (surrogate endpoints). New compounds are used without evidence of clinical benefit in millions of people worldwide. There is also an increasing number of examples on surrogate end point fallacies related to non-drug interventions (psychological, nursing, educational, social policy).

Endpoint Determination↗
PubMed2006

Flexible intensive insulin therapy in adults with type 1 diabetes and high risk for severe hypoglycemia and diabetic ketoacidosis.

OBJECTIVE: Diabetes treatment and teaching programs (DTTPs) for type 1 diabetes, which teach flexible intensive insulin therapy to enable dietary freedom, have proven to be safe and effective in routine care. This study evaluates DTTP outcomes in patients at high risk for severe hypoglycemia and severe ketoacidosis. RESEARCH DESIGN AND METHODS: There were 96 diabetes centers that participated between 1992 and 2004. A total of 9,583 routine-care patients with type 1 diabetes were examined before and 1 year after a DTTP. History of repeated severe hypoglycemia/severe ketoacidosis was an indication for DTTP participation. Before-after analyses were performed for subgroups of patients with three or more episodes of severe hypoglycemia or two or more episodes of severe ketoacidosis during the year before a DTTP. Main outcome measures were GHb, severe hypoglycemia, severe ketoacidosis, and hospitalization. RESULTS: A total of 341 participants had three or more episodes of severe hypoglycemia the year before a DTTP. Mean baseline GHb was 7.4 vs. 7.2% after the DTTP, incidence of severe hypoglycemia was 6.1 vs. 1.4 events x patient(-1) x year(-1), and hospitalization was 8.6 vs. 3.9 days x patient(-1) x year(-1). In mixed-effects models taking effects of centers and diabetes duration into account, mean difference was -0.3% (95% CI -0.5 to -0.1%; P = 0.0006) for GHb and -4.7 events x patient(-1) x year(-1) (-5.4 to -4; P < 0.0001) for severe hypoglycemia. A total of 95 patients had two or more episodes of severe ketoacidosis. GHb was 9.4% at baseline versus 8.7% after DTTP; incidence of severe ketoacidosis was 3.3 vs. 0.6 events x patient(-1) x year(-1), and hospitalization was 19.4 vs. 10.2 days x patient(-1) x year(-1). In linear models with diabetes duration as the fixed effect, the adjusted mean difference was -2.7 events x patient(-1) x year(-1) (95% CI -3.3 to -2.1; P < 0.0001) for severe ketoacidosis and -8.1 days (-12.9 to -3.2; P = 0.0014) for hospitalization. CONCLUSIONS: Patients at high risk for severe hypoglycemia or severe ketoacidosis may benefit from participation in a standard DTTP for intensive insulin therapy and dietary freedom.

Adult↗
PubMed2006

Communicating "bad news" about screening results to patients.

There is much enthusiasm for cancer screening in the United States. In Germany, promotion of cancer screening is growing, often including biased and misleading information. Consequently, the risks of cancer and death from cancer are overestimated, while the harms of screening such as false positive results and over-treatment are underestimated. However, high-quality evidence-based information on breast cancer screening and colorectal cancer screening is available in Germany.

Colorectal Neoplasms↗
PubMed2005

Predicting the risk of falling--efficacy of a risk assessment tool compared to nurses' judgement: a cluster-randomised controlled trial [ISRCTN37794278].

BACKGROUND: Older people living in nursing homes are at high risk of falling because of their general frailty and multiple pathologies. Prediction of falls might lead to an efficient allocation of preventive measures. Although several tools to assess the risk of falling have been developed, their impact on clinically relevant endpoints has never been investigated. The present study will evaluate the clinical efficacy and consequences of different fall risk assessment strategies. STUDY DESIGN: Cluster-randomised controlled trial with nursing home clusters randomised either to the use of a standard fall risk assessment tool alongside nurses' clinical judgement or to nurses' clinical judgement alone. Standard care of all clusters will be optimised by structured education on best evidence strategies to prevent falls and fall related injuries. 54 nursing home clusters including 1,080 residents will be recruited. Residents must be > or = 70 years, not bedridden, and living in the nursing home for more than three months. The primary endpoint is the number of participants with at least one fall at 12 months. Secondary outcome measures are the number of falls, clinical consequences including side effects of the two risk assessment strategies. Other measures are fall related injuries, hospital admissions and consultations with a physician, and costs.

Accidental Falls↗
PubMed2005

Evidence-based patient information about treatment of multiple sclerosis--a phase one study on comprehension and emotional responses.

OBJECTIVE: This study analysis the comprehension and emotional responses of people suffering from multiple sclerosis when provided with an evidence-based information module. It is a core module of a comprehensive decision aid about immunotherapy. The core module is designed to enable patients to process scientific uncertainty without adverse effects. It considers existing standards for risk communication and presentation of data. METHODS: Using a mailing approach we investigated 169 patients with differing courses of disease in a before-after design. Items addressed the competence in processing relative and absolute risk information and patients' emotional response to the tool, comprising grade of familiarity with the information, understanding, relevance, emotional arousal, and certainty. RESULTS: Overall, numeracy improved (p < 0.001), although 99 of 169 patients did not complete the numeracy task correctly. Understanding depended on the relevance related to the course of disease. A moderate level of uncertainty was induced. No adverse emotional responses could be shown, neither in those who did comprehend the information, nor in those who did not develop numeracy skills. CONCLUSION: In conclusion, the tool supports people suffering from multiple sclerosis to process evidence-based medical information and scientific uncertainty without burdening them emotionally. PRACTICE IMPLICATIONS: This study is an example for the documentation of an important step in the development process of a complex intervention.

Adult↗
PubMed2005

Increased use of hip protectors in nursing homes: economic analysis of a cluster randomized, controlled trial.

OBJECTIVES: To assess the cost-efficacy of an intervention program aimed at reducing hip fractures. DESIGN: Economic evaluation within an 18-month cluster randomized trial. SETTING: Forty-nine nursing homes in Hamburg, Germany. PARTICIPANTS: Residents with a high risk of falling (intervention group (IG), n=459; control group (CG), n=483). INTERVENTION: Education session for nurses, who subsequently educated residents, and provision of three hip protectors per resident. CG care was optimized by providing brief information to nurses about hip protectors and providing two protectors per nursing home for demonstration purposes. MEASUREMENTS: Main outcomes were hip fractures, costs, and incremental cost-effectiveness ratio (ICER). RESULTS: The intervention was effective in reducing hip fractures (21 in the IG vs 42 in the CG) and resulted in a cost difference of 51 dollars per participant in favor of the CG (95% confidence interval covering cost saving of 242 dollars to cost expense of 325 dollars). Costs per additional hip fracture avoided were 1,234 dollars. Sensitivity analyses aimed at investigating robustness of the results to a real practice implementation scenario resulted in ICERs varying from 439 dollars to 1,693 dollars. Taking into account lower hip protector reimbursement levels, the intervention program would be cost saving (break-even point within the base case analysis=22 dollars per hip protector). CONCLUSION: A program consisting of education and provision of hip protectors might produce a slight increase in costs or might even be cost saving if the price of the hip protector could be decreased.

Aged↗
PubMed2005

[Criteria for evidence-based patient information].

Evidence-based patient information (EBPI) is a prerequisite for informed patient choice. However, there is as yet no discussion as to what can be expected of EBPI. The present paper provides an overview of the criteria presently used or discussed for the development of EBPI. Ethics guidelines demand that EBPI are offered and made available to all patients. The presentation of information should be clear and consider risk communication as a source of framing of data. Patients should be involved in the process of development and evaluation.

Evidence-Based Medicine↗
PubMed2004

[Cardiovascular risk assessment for informed decision making. Validity of prediction tools].

BACKGROUND AND PURPOSE: Patient involvement in health care decisions is increasingly requested. The authors investigated whether currently available assessment tools for prediction of cardiovascular risk can be used for individual risk prediction as a basis of informed decision making. METHODS: The authors searched for risk assessment tools and respective validation studies in Medline (until August 16, 2004) and the Cochrane Library (issue 2/2004). The following criteria were used for evaluation of prognostic studies: (1) discrimination between risk groups; (2) predictive values; (3) prognostic agreement; (4) transferability across populations. RESULTS: A total of twelve assessment tools were identified. The Framingham function, Sheffield Tables, Canadian Tables, Framingham Categorial, New Zealand, Joint British, and European Charts (1994 and 1998) are based on the Framingham Study; PROCAM Risk Score, UKPDS Risk Engine, and SCORE Risk Charts use different source data. Framingham-based instruments overestimate cardiovascular risk of Central-European populations by at least 30%, with substantial regional variation even within a country (between 30% and 100%, British Regional Heart Study). Therefore, prior to application the assessment tools would need recalibration using regional data of cardiovascular mortality and adjustment for social class differences. Published sensitivity, specificity, and C-statistics for external validation (area under the curve [AUC] approximately 0.6) are clearly inferior to internal validation (AUC approximately 0.8). Agreement between instruments beyond chance is moderate (kappa approximately 0.5). No studies on external validation could be identified for the new European SCORE Risk Charts and UKPDS Risk Engine. CONCLUSION: Validation of currently available assessment tools for cardiovascular risk prediction is inadequate. Uncritical use may lead to substantial under- or overestimation of individual cardiovascular risk and inappropriate treatment decisions.

Adult↗
PubMed2004

Explaining computation of predictive values: 2 x 2 table versus frequency tree. A randomized controlled trial [ISRCTN74278823].

BACKGROUND: Involving patients in decision making on diagnostic procedures requires a basic level of statistical thinking. However, innumeracy is prevalent even among physicians. In medical teaching the 2 x 2 table is widely used as a visual help for computations whereas in psychology the frequency tree is favoured. We assumed that the 2 x 2 table is more suitable to support computations of predictive values. METHODS: 184 students without prior statistical training were randomised either to a step-by-step self-learning tutorial using the 2 x 2 table (n = 94) or the frequency tree (n = 90). During the training session students were instructed by two sample tasks and a total of five positive predictive values had to be computed. During a follow-up session 4 weeks later participants had to compute 5 different tasks of comparable degree of difficulty without having the tutorial instructions at their disposal. The primary outcome was the correct solution of the tasks. RESULTS: There were no statistically significant differences between the two groups. About 58% achieved correct solutions in 4-5 tasks following the training session and 26% in the follow-up examination. CONCLUSIONS: These findings do not support the hypothesis that the 2 x 2 table is more valuable to facilitate the calculation of positive predictive values than the frequency tree.

Adult↗
PubMed2004

Risk information--barrier to informed choice? A focus group study.

OBJECTIVES: To study consumers' information needs for informed choice on colorectal cancer screening, and to develop and evaluate information material that is evidence-based and communicates benefit as well as lack of benefit and risks as natural frequencies. METHODS DESIGN: Focus group study; during a first round consumers' needs and attitudes were surveyed, in a second round the information material was evaluated. The study was carried out in Hamburg, Germany. PARTICIPANTS: 50 women and men, 40 years or older without colorectal diseases. RESULTS: Consumers opted for traditional information that advises and guides them. If consumers were nevertheless given evidence-based information that considers the defined criteria it evoked cognitive dissonance which consumers tried to cope with by devaluating, minimising and not noticing the information. Cognitive dissonance inhibits processing of information. Researchers are confronted with a dilemma to either respect consumers' requests or to facilitate informed choice. CONCLUSION: Cognitive dissonance may be a barrier to informed choice. This should be considered when aiming at communicating risk information.

Adaptation, Psychological↗
PubMed2004

Predictors of adherence to the use of hip protectors in nursing home residents.

OBJECTIVES: To assess predictors of hip-protector use in nursing home residents under usual-care conditions and after intervention consisting of structured education of nurses and nursing home residents and provision of free hip protectors. DESIGN: Nested cohort analyses within a cluster randomized, controlled trial with 18 months follow-up. SETTING: Forty-nine nursing home clusters in Hamburg, Germany. PARTICIPANTS: Residents with at least one fall during the study period (intervention group, n=237; usual-care group, n=274). MEASUREMENTS: Use of hip protector while falling. Regression analyses were performed for each of the two cohorts of fallers using the time to the first fall without hip protector as the dependent variable. Predefined nursing home cluster-related parameters (center, staffing ratio, proportion of registered nurses in nursing staff, hip-protector use before study period) and resident-related parameters (sex, history of falls and fractures, fear of falling, urinary incontinence, use of walking aid, degree of disablement) were considered as explanatory variables. RESULTS: Under usual care, 97% of fallers (n=266), compared with 62% (n=148) in the intervention group, experienced at least one fall without hip protection. Using Cox proportional hazards models with and without frailty parameter (random cluster effect), the following predictors were identified: intervention group: use of walking aid, hazard ratio (HR)=1.53 (95% confidence interval (CI):0.98-2.39) and no urinary incontinence, HR=1.47 (95% CI:1.03-2.09); usual care: nursing staff per 10 residents, HR=0.78 (95% CI=0.63-0.96); high degree of disablement, HR=1.38 (95% CI=1.06-1.80); strong fear of falling, HR=0.78 (95% CI=0.60-1.02). The nursing home cluster was a significant predictor in the control group (P=.029), but not in the intervention group (P=.100). CONCLUSION: Only a few and weak predictors of hip-protector use of questionable relevance could be identified in both groups. Future research should concentrate on the implementation of interventions of proven efficacy, such as provision of hip protectors combined with structured education of staff and residents.

Accidental Falls↗
PubMed2004

Decisional role preferences, risk knowledge and information interests in patients with multiple sclerosis.

OBJECTIVE: Shared decision making is increasingly recognized as the ideal model of patient-physician communication especially in chronic diseases with partially effective treatments as multiple sclerosis (MS). To evaluate prerequisite factors for this kind of decision making we studied patients' decisional role preferences in medical decision making, knowledge on risks, information interests and the relations between these factors in MS. METHODS: After conducting focus groups to generate hypotheses, 219 randomly selected patients from the MS Outpatient Clinic register (n = 1374) of the University Hospital Hamburg received mailed questionnaires on their knowledge of risks in MS, their perception of their own level of knowledge, information interests and role preferences. RESULTS: Most patients (79%) indicated that they preferred an active role in treatment decisions giving the shared decision and the informed choice model the highest priority. MS risk knowledge was low but questionnaire results depended on disease course, disease duration and ongoing immune therapy. Measured knowledge as well as perceived knowledge was only weakly correlated with preferences of active roles. Major information interests were related to symptom alleviation, diagnostic procedures and prognosis. CONCLUSION: Patients with MS claimed autonomous roles in their health care decisions. The weak correlation between knowledge and preferences for active roles implicates that other factors largely influence role preferences.

Adult↗
PubMed2003

[Evidence-based treatment and education programs--evaluation of complex interventions].

Patient education and treatment programmes are complex interventions that require a multiphased stepwise evaluation. The continuum of increasing evidence of effectiveness of structured treatment and teaching programmes for diabetes and hypertension as implemented in Germany is presented, and the indispensable components of the program and the conditions of their effective implementation are described.

Education, Medical↗