This study aims to develop and to validate a standardised German-language instrument for measuring experienced financial effects of a cancer diagnosis and therapy in a cross-sectional bi-centre study. Obtained data will make the patient-related description of financial difficulties more comprehensible, communicable and addressable in the future, e.g. by offering targeted advisory aids or considering financial effects in health technology assessments.

Methods and analysis:

Phase 1: Construct definition and item generation

Preliminary study:

The preliminary study aims to identify dimensions, topics and risk factors that are relevant for the assessment of financial effects through qualitative interviews with patients, focus group discussions with potential users of a new instrument (social services, HTA-institutions, payers) and a systematic literature review.

Preliminary questionnaire:

In order to derive a pre-final questionnaire, the aim of this part of the study is to define the construct of financial effects and to generate a list of appropriate indicators for measuring financial effects based on the results available from the literature. The pre-final questionnaire will be peer-reviewed by the interdisciplinary project team (oncology/medical ethics, health economics, methods of empirical social research).

Phase 2: Questionnaire Piloting and Validation

Cognitive pre-test:

A cognitive pre-test of the pre-final questionnaire is conducted to examine comprehension of questions and response option and identify any potential problems respondents would have to understand the questions and to respond to them. The results are used in order to further optimize the first draft of the questionnaire.

Quantitative evaluation and validation:

Quantitative evaluation and validation of the developed questionnaire will be performed based on two studies on the target population by determining the distribution parameters of the indicators and their measurement characteristics. In the first study, the pre-final questionnaire will be tested and after adjustment, the final version will be applied in study 2. Participants of the first study (n=100) will be surveyed again within the second study (n=400 participants), while data of the additional participants (n=300) in study 2 will be measured at a single time point.

For validation purposes, additional scales measuring similar and unrelated constructs, as well as criteria (external concepts affected by financial effects) will be included in the questionnaire. Validity will be assessed by subsequent examining of different relationships between the developed instrument and predefined third variables and criteria. Factorial validity will be examined by factor analyses. Furthermore reliability and test-fairness of the instrument will be assessed through further psychometric testing.

Phase 3: Further applicability of the questionnaire To formulate well-founded recommendations for the use of the instrument, a pilot screening program for social services is evaluated through qualitative interviews with representatives of social services and patients regarding practicability of the instrument. A synthesis of all project results will translate into overall recommendations within the clinical and regulatory context.

Inclusion Criteria:

• Any type of historically or cytological confirmed solid cancer or haematological malignancy with an ECOG-Status <2 and at least two month of cancer related therapy
• Patients are treated at the day care unit or ambulances of the NCT Heidelberg or oncological ward B100 at Jena University Hospital

Exclusion Criteria:

• Patients younger than 18 years old
• Patients who refuse or withdraw from informed consent
• No sufficient level of German language

Patients with all types of cancer who have undergone at least two months of cancer related therapy with an ECOG Status < 2, who are treated at the day care unit and ambulances of the NCT Heidelberg or conservative day care unit and oncological ward B100, Jena University Hospital.