Table 1.

Measures

Topic	Subcategory	Number of items	Scoring	Alpha	Reference	Description of questions/examples
1. Sociodemographic characteristics	n/a	n/a	n/a	n/a	n/a	Age, gender, race, specialty
2. Practice characteristics	n/a	n/a	n/a	n/a	n/a	specialty, number and type of gene tests ordered, experience with patient care
3. Information giving	a. Topics discussed	5	5-point scale: always to never	n/a	5 self-developed statements on how often topics are discussed when providing cancer genetic counselling	e.g. ‘Benefits and limitations of close cancer surveillance’
	b. Skills perception	13	13–65 (5-point scale: strongly agree to strongly disagree). A higher total score means a more positive perception of one’s info giving skills	0.88	10 items are adapted from an unpublished questionnaire used in the radiotherapy setting and 3 items are based on Keating et al. [4]	e.g. ‘I am comfortable discussing hereditary cancer issues with my patients’
4. Decision-making	a. Attitude towards patient autonomy	14		See Table 3	Adaptation of the Ideals of Patient Autonomy Scale (Stiggelbout et al 2012) [30]. Our adapted version includes 3 subscales (see Table 3)	e.g. ‘If the patient does not want to receive information about risks, the healthcare provider should respect this’
	b. Attitude towards responsibility	1	5-point scale (strongly agree to strongly disagree)		Self-developed. This item is added to the adapted IPAS in Table 3	‘It is my responsibility to help a patient make a decision about genetic testing’
	c. Skills perception	6	5-point scale (difficult to easy)		Self-developed	Rate the difficulty of several communication tasks related to decision-making, e.g. ‘involving the patient in the decision’
5. Enabling disease and treatment related behaviors	a. Attitude towards responsibility	2	5-point scale (strongly agree to strongly disagree)		Self-developed	e.g. ‘It is my responsibility to discuss preventive behaviors such as prophylactic surgeries and/or regular cancer screening’
	b. Attitude towards future developments	2	5-point scale (strongly agree to strongly disagree)		Self-developed and one item based on Shields et al. [5]	e.g. ‘I am optimistic that genetic research will lead to significant improvements in the treatment of complex traits’
6. Managing emotions	a. Skills perception	7	5-point scale (difficult to easy)		Self-developed	Rate the difficulty of several communication tasks related to managing emotions, e.g. ‘preparing the patient for negative emotions’
	b. Attitude	2	5-point scale (strongly agree to strongly disagree)		Self-developed	e.g. ‘It is my responsibility to manage emotions that patients experience during genetic counseling’
7. Education	a. Received training	7	2 Yes/No, 2 multiple-options, 2 open questions, 1 statement with 5-point scale (strongly agree to strongly disagree)		Questions based on Shield et al. [5] and on remarks in Zon et al. [7]	e.g. ‘Did you receive specific training about how to communicate with patients about hereditary cancer?’
	b. Use of risk models	3	2 Yes/No, 1 multiple-options		Questions based on remarks in Zon et al. [7]	e.g. ‘Which web-based risk assessment models do you use?’
8. Knowledge	a. General perception	4	4-point scale (Very good to very poor)		Based on Klitzman et al. [10]	e.g. ‘My knowledge about hereditary cancer genetics is…’
	b. Confidence	2	5-point scale (Strongly agree to strongly disagree)		Based on Shields et al. [5]	e.g. ‘I am confident in my ability to interpret a variant genetic test result’
	c. Objective knowledge	9	3-point scale (True/False/Do not know)		Several items are derived from Erblich et al. [31] and 3 items are derived from a study among FAP-patients of one of the authors (Douma)