Fülöp Scheibler

Randomized Controlled Trials on PET: A Systematic Review of Topics, Design, and Quality

Randomized controlled trials (RCTs) add important information to diagnostic accuracy studies in the evaluation of PET and PET/CT. We evaluated how many RCTs on PET existed, which clinical topics they addressed, and what their design and quality were. Methods: We searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials (Clinical Trials) up to August 2010. We also searched in ClinicalTrials.gov and the International Clinical Trials Registry Platform for ongoing RCTs up to March 2011. Titles and abstracts and full texts were screened independently by 2 reviewers. Study characteristics were extracted with standard extraction sheets for ongoing and published RCTs, and risk of bias was assessed for published ones. Results: We identified 54 RCTs, 12 of which were published. The main topics in published studies were non–small cell lung cancer and colorectal cancer; only 3 were conducted in nononcologic fields (this trend was similar in ongoing studies, in which the most common topic was Hodgkin disease). The main indications in the oncologic PET studies were staging in published studies and restaging (mostly including an early assessment of treatment response) in ongoing ones. All except 1 of the published studies applied a marker-based strategy design, whereas about 43% (18/42) of ongoing studies use a more efficient design (Enrichment Design or Marker by Treatment Interaction Design). Conclusion: A relatively high number of ongoing RCTs of PET in several oncologic fields are expected to produce robust results over the next few years. For nononcologic topics, further high-quality studies are still needed to ascertain the benefit of this technique for patients. As funding is usually difficult in nondrug topics, alternative concepts of funding, which should also involve the manufacturers of diagnostic devices, but also more efficient study designs, should be applied to bridge the evidence gap on PET in the near future.

Die Einbeziehung von Patienten in die Behandlung

ZusammenfassungDie partnerschaftliche Einbeziehung von Patienten in Diagnoseerstellung und Behandlungsentscheidungen gewinnt auch in Deutschland zunehmend an Bedeutung. Unter dem Begriff Shared decision-making konnte in zahlreichen internationalen Studien gezeigt werden, dass Patienten, die sich in ihre Behandlung einbezogen fühlen, zufriedener sind und bessere Ergebnisse erzielen, als jene, die lediglich passiv die Anweisungen des medizinischen Personals befolgen. Für den deutschsprachigen Raum existiert derzeit noch kein validiertes Messinstrument, um das Konzept des Shared decision-making adäquat zu erfassen. Ziel vorliegender Studie war es daher, ein amerikanisches Instrument zu übersetzen und anhand einer deutschen Stichprobe zu validieren. Die „perceived involvement in care scales“ (PICS) messen die wahrgenommene Einbeziehung von Patienten in die Therapie. Die drei Subskalen der deutschen PICS-Version erfassen die „Patientenaktivierung durch die Ärzte“ (PAA), das „aktive Informationsverhalten des Patienten“ (AIP) und die „Entscheidungsteilnahme des Patienten“ (ETP) aus dessen subjektiver Perspektive. Die auf den Daten einer repräsentativen Befragung von 230 Patienten des Universitätsklinikums zu Köln (131 Männer und 97 Frauen) im Alter von 19 bis 89 Jahren basierende teststatistische Überprüfung zeigt, dass die deutschen PICS reliable, valide und ökonomisch einsetzbare Erhebungsinstrumente darstellen. Lediglich die Plausibilitätstests der dritten Subskala lieferten mit unseren Erwartungen inkonsistente Ergebnisse, die wahrscheinlich auf kulturelle Unterschiede zwischen der Arzt-Patienten-Interaktion in den USA und in Deutschland zurückzuführen sind. Die Entscheidungsteilnahme des Patienten-Skala wurde daher in einer veränderten Fassung an einer Stichprobe von 720 Patienten aus vier Krankenhäusern erneut getestet und erwies sich in dieser Untersuchung ebenfalls als valide. Die mit den PICS erfasste „wahrgenommene Einbeziehung“ erweist sich als weitestgehend unabhängig von soziodemographischen, sozioökonomischen oder krankheitsspezifischen Variablen.AbstractPatients as partners in diagnostic and treatment decisions are recently gaining importance in Germany. Several international studies on shared decision making have shown positive effects of perceived involvement in care on patient satisfaction and other important outcomes. As no valid measuring-instrument exists for the German-language yet the aim of this study was to translate an American instrument and validate it on the base of a German sample. The German “Perceived Involvement in Care Scales” (PICS) examine three relatively distinct factors: doctor facilitation of patient involvement, level of information exchange and patient participation in decision making. The questionnaire was sent to a sample of in-house patients of the University Hospital of Cologne. The 230 returned questionnaires have been filled out by 131 men and 97 women in an age-range between 19 and 89 years. The statistical analyses proved the German PICS to be reliable, valid and effectively applicable instruments. Only the tests of plausibility for the third subscale produced results that were not consistent with our expectations. These results are probably due to cultural differences between the patient-physician-interaction in the USA and Germany. The patient-decision-making-subscale was therefore modified and tested on the base of a sample of 720 patients of four hospitals. The results indicate validity of this instrument. We did not find any correlation between perceived involvement and socio-demographic, socio-economic or illness-specific variables, in our data.

F-18-fluoro-2-deoxyglucose positron emission tomography (PET) and PET/computed tomography imaging in primary staging of patients with malignant melanoma: a systematic review

PurposeThe aim of this systematic review was to systematically assess the potential patient-relevant benefit (primary aim) and diagnostic and prognostic accuracy (secondary aim) of positron emission tomography (PET) and PET/computed tomography (CT) in primary staging of malignant melanoma. This systematic review updates the previous evidence for PET(/CT) in malignant melanoma.Materials and methodsFor the first aim, randomized controlled trials (RCTs) investigating patient-relevant outcomes and comparing PET and PET(/CT) with each other or with conventional imaging were considered. For the secondary aim, a review of reviews was conducted, which was amended by an update search for primary studies. MEDLINE, EMBASE and four databases of the Cochrane Library were searched. The risk of bias was assessed using a modified QUADAS tool.ResultsNo RCTs investigating the patient-relevant benefit of PET(/CT) and no prognostic accuracy studies were found. Seventeen diagnostic accuracy studies of varying quality were identified. For patients with American Joint Committee on Cancer (AJCC) stages I and II, sensitivity mostly ranged from 0 to 67%. Specificity ranged from 77 to 100%. For AJCC stages III and IV, sensitivity ranged from 68 to 87% and specificity from 92 to 98%.ConclusionThere is currently no evidence of a patient-relevant benefit of PET(/CT) in the primary staging of malignant melanoma. RCTs investigating patient-relevant outcomes are therefore required. The diagnostic accuracy of PET(/CT) appears to increase with higher AJCC stages.

A descriptive review on methods to prioritize outcomes in a health care context

Evidence synthesis has seen major methodological advances in reducing uncertainty and estimating the sizes of the effects. Much less is known about how to assess the relative value of different outcomes.

[Shared decision-making as a new quality indicator in nephrology: a nationwide survey in Germany].

ZusammenfassungHintergrund und Ziel:Partizipative Entscheidungsfindung (Shared Decision-Making) gewinnt als Modell der Arzt-Patienten-Beziehung auch im deutschen Gesundheitssystem zunehmend an Bedeutung. Insbesondere im Bereich chronischer Erkrankungen erwartet man sich von diesem Konzept mittel- bis langfristige Verbesserungen der Behandlungsergebnisse. Bislang liegen der deutschen Versorgungsforschung jedoch kaum empirische Daten zum Stand und zu den Entwicklungstendenzen der partizipativen Entscheidungsfindung vor. Diese Studie liefert aktuelle Ergebnisse zu dieser Fragestellung aus einer deutschlandweiten Befragung von terminal niereninsuffizienten Patienten.Methodik:Im Rahmen des Programms Qualität in der Nephrologie (QiN) wurden in einer schriftlichen, deutschlandweiten Erhebung 6 614 Patienten mit terminaler Niereninsuffizienz befragt. Der Fragebogen enthielt ein zuvor übersetztes und validiertes Instrument zur Erfassung der wahrgenommenen Einbeziehung in die Therapie (PICS).Ergebnisse:82% der Befragten fühlen sich durch ihre Ärzte für eine Beteiligung an Entscheidungen motiviert. 81% der Patienten informieren sich aktiv bei ihren Ärzten über ihre Erkrankung und Behandlungsmöglichkeiten. 69% geben an, dass eine gemeinsame Entscheidungsfindung von Arzt und Patient stattgefunden hat. Das Lebensalter, die Dialysejahre und das Geschlecht stehen im Zusammenhang mit der wahrgenommenen Einbeziehung.Schlussfolgerung:Dieser Aufsatz bietet eine valide Grundlage für die prospektive Erforschung der partizipativen Entscheidungsfindung in der Behandlung der terminalen Niereninsuffizienz. Die Ergebnisse der vorliegenden Studie deuten auf eine hohe Bereitschaft von Dialysepatienten hin, sich aktiv am Prozess der Entscheidungsfindung zu beteiligen. Spezifische Patientencharakteristika und die Präferenzen der Patienten sollten nicht nur bei der alltäglichen klinischen Interaktion mit den Patienten Berücksichtigung finden. Sie könnten darüber hinaus im Rahmen der Qualitätssicherung systematisch erfasst und als Verbesserungspotential genutzt werden.AbstractBackground and Purpose:Shared decision-making (SDM) as a model in physician-patient interaction is gaining relevance in the German health system. By applying this model, mid- and long-term improvements are expected especially in the outcomes of chronic diseases. Up to now, there has hardly been any empirical data available in German health services research regarding the state and development of SDM. This study establishes a baseline and provides actual data on this subject based on a German-wide survey of end-stage renal disease (ESRD) patients.Methods:Standardized German-wide survey of 6,614 patients with ESRD. The questionnaire included an instrument to measure the patients’ perceived involvement in care (PICS) which had been translated and validated before.Results:82% of the questioned patients feel their physicians facilitated involvement in decision making. 81% of the patients actively inform themselves concerning their disease and treatment options. 69% state that SDM has taken place. Age, years on dialysis and gender correlate with perceived involvement.Conclusion:This paper provides a valid baseline for the prospective research of SDM in ESRD. The results indicate that dialysis patients are willing to participate in the process of medical decision-making. Characteristics and preferences of the patients should be taken into account not only in everyday clinical interactions. They could be monitored systematically within the framework of quality management and used as potential for quality improvement.

Evidence-Based Assessment of PET in Germany

TO THE EDITOR: The article by Weber (1) offers some interesting interpretations of how PET is currently being assessed not only in Germany by the Institute for Quality and Efficiency in Health Care (IQWiG) but also in other countries. However, the author made an incorrect statement about IQWiG that needs to be clarified. IQWiG does not “typically give grants to small companies specialized in preparing systematic reviews.” IQWiG has actually established a diligent process of selecting and commissioning external partners who have profound expertise both in evidence-based methodology and in the clinical field concerned. In most cases, IQWiG’s external experts are based or have previously worked at highly reputed universities. This can be easily checked on our Web site. However, the full range of expertise involved in IQWiG reports is not presented on the Web site, as some external experts prefer not to be named. In addition, we would like to note that every report on PET published by IQWiG was prepared in collaboration with at least one experienced clinician.

Partizipative Entscheidungsfindung als neuer Qualitätsindikator in der Nephrologie

ZusammenfassungHintergrund und Ziel:Partizipative Entscheidungsfindung (Shared Decision-Making) gewinnt als Modell der Arzt-Patienten-Beziehung auch im deutschen Gesundheitssystem zunehmend an Bedeutung. Insbesondere im Bereich chronischer Erkrankungen erwartet man sich von diesem Konzept mittel- bis langfristige Verbesserungen der Behandlungsergebnisse. Bislang liegen der deutschen Versorgungsforschung jedoch kaum empirische Daten zum Stand und zu den Entwicklungstendenzen der partizipativen Entscheidungsfindung vor. Diese Studie liefert aktuelle Ergebnisse zu dieser Fragestellung aus einer deutschlandweiten Befragung von terminal niereninsuffizienten Patienten.Methodik:Im Rahmen des Programms Qualität in der Nephrologie (QiN) wurden in einer schriftlichen, deutschlandweiten Erhebung 6 614 Patienten mit terminaler Niereninsuffizienz befragt. Der Fragebogen enthielt ein zuvor übersetztes und validiertes Instrument zur Erfassung der wahrgenommenen Einbeziehung in die Therapie (PICS).Ergebnisse:82% der Befragten fühlen sich durch ihre Ärzte für eine Beteiligung an Entscheidungen motiviert. 81% der Patienten informieren sich aktiv bei ihren Ärzten über ihre Erkrankung und Behandlungsmöglichkeiten. 69% geben an, dass eine gemeinsame Entscheidungsfindung von Arzt und Patient stattgefunden hat. Das Lebensalter, die Dialysejahre und das Geschlecht stehen im Zusammenhang mit der wahrgenommenen Einbeziehung.Schlussfolgerung:Dieser Aufsatz bietet eine valide Grundlage für die prospektive Erforschung der partizipativen Entscheidungsfindung in der Behandlung der terminalen Niereninsuffizienz. Die Ergebnisse der vorliegenden Studie deuten auf eine hohe Bereitschaft von Dialysepatienten hin, sich aktiv am Prozess der Entscheidungsfindung zu beteiligen. Spezifische Patientencharakteristika und die Präferenzen der Patienten sollten nicht nur bei der alltäglichen klinischen Interaktion mit den Patienten Berücksichtigung finden. Sie könnten darüber hinaus im Rahmen der Qualitätssicherung systematisch erfasst und als Verbesserungspotential genutzt werden.AbstractBackground and Purpose:Shared decision-making (SDM) as a model in physician-patient interaction is gaining relevance in the German health system. By applying this model, mid- and long-term improvements are expected especially in the outcomes of chronic diseases. Up to now, there has hardly been any empirical data available in German health services research regarding the state and development of SDM. This study establishes a baseline and provides actual data on this subject based on a German-wide survey of end-stage renal disease (ESRD) patients.Methods:Standardized German-wide survey of 6,614 patients with ESRD. The questionnaire included an instrument to measure the patients’ perceived involvement in care (PICS) which had been translated and validated before.Results:82% of the questioned patients feel their physicians facilitated involvement in decision making. 81% of the patients actively inform themselves concerning their disease and treatment options. 69% state that SDM has taken place. Age, years on dialysis and gender correlate with perceived involvement.Conclusion:This paper provides a valid baseline for the prospective research of SDM in ESRD. The results indicate that dialysis patients are willing to participate in the process of medical decision-making. Characteristics and preferences of the patients should be taken into account not only in everyday clinical interactions. They could be monitored systematically within the framework of quality management and used as potential for quality improvement.

Mehrfachauswertungen qualitativer Daten mit Hilfe eines deduktiven Schemas und MAXqda

In diesem Beitrag soll ein theoriegeleitetes Ordnungs- und Auswertungsschema vorgestellt werden, das zur Vereinfachung der Auswertung von Leitfadeninterviews im Bereich der Qualitatssicherung innerhalb der Gesundheitssystemforschung entwickelt wurde. Das Verfahren kombiniert das Struktur-ProzessErgebnis-Modell (Donabedian) mit der Akteur-Situation-Dimension (Esser/Coleman). Es hilft dem Forscher bei der Kategorisierung von Interviewsequenzen. Die Vorteile dieses Schemas liegen vor allem in der universellen Anwendbarkeit und der Zeitersparnis bei mehrfacher Auswertung desselben Datenmaterials (z.B. bezuglich unterschiedlicher Dimensionen bei der Entwicklung eines Fragebogens).

Consensus About Objectives

I do not agree with the authors (1) that shared decision making (SDM) should primarily be used to improve patient-relevant, disease-related endpoints. According to international consensus, the aim of SDM is to reach “informed decisions”—that is, decisions based on complete information about all alternatives, including doing nothing, which reflect the subjective preferences of patients (2, 3). The authors consider surrogate endpoints, the validity of which is either not, or not consistently given, as relevant for patients; this includes for instance HbA1c in type 2 diabetes mellitus, total cholesterol and LDL cholesterol after acute coronary syndrome, adherence of patients with bronchial asthma, or blood pressure in arterial hypertension. In particular, only increasing adherence or compliance cannot be, in my view, the purpose of SDM. It is unclear why, of all terms, the MeSH term “shared decision making” was not considered in the literature search. Likewise, it is unclear why “decision aids” (or “patient decision support technologies”) were excluded (for instance, see [4]). I completely agree with the authors, however, that the theoretical concept of SDM should be clarified, and that a consensus about the objectives (and objectives criteria) should be reached.

The Role of PET and PET-CT Scanning in Assessing Response to Neoadjuvant Therapy in Esophageal Carcinoma A Systematic Review

BACKGROUND The response to neoadjuvant (radio-)chemotherapy for esophageal carcinoma is often assessed with the aid of positron-emission tomography (PET), either alone or in combination with computed tomography (PET-CT). In this review, we discuss the diagnostic validity and clinical benefit of these imaging techniques. METHODS We systematically searched the Medline, Embase, and Cochrane Library databases for randomized controlled trials (RCTs) and controlled clinical trials (CCTs) comparing PET-CT with conventional techniques such as endosonography and CT. We then determined the diagnostic validity of these methods on the basis of information from published systematic reviews, updated with further information from more recent primary studies. RESULTS We did not find any RCTs that addressed the question of the patient-relevant benefit of PET-CT. We found 20 studies of diagnostic methods, carried out on a total of 854 patients, of whom 82.2% were male. These studies had a high potential for bias. In two of them, PET-CT was directly compared with endosonography or CT. Estimates of sensitivity and specificity varied widely across studies. 54% of all patients (median value across studies) had no histopathological response to therapy at the end of treatment. Taking a reduction of the standard uptake value (SUV) by at least 35% as a threshold criterion, we found that the median negative predictive value of PET across all studies was 86.5. CONCLUSION There is no robust evidence for a patient-relevant benefit of PET and PET-CT in patients with esophageal carcinoma. PET could potentially be used to distinguish treatment responders from non-responders after the first cycle of treatment. RCTs with patient-relevant endpoints will be needed in order to determine whether this is useful.