Typical referral situations
Of the 390 referrals (307, 79% women), 190 (49%) originated from primary and 173 (44%) from secondary care, 27 (7%) originating from outside Devon. The majority (295, 76%) of individuals tested had normal results, whilst 94 (24%) were heterozygous and one (0.3%) was homozygous for FVL. The most common reasons for referral were: (i) personal history of deep vein thrombosis (DVT) (115/390, 30%); (ii) family history of DVTs (74/390, 19%); (iii) family history of genetic thrombophilia (67/390, 17%); and (iv) recurrent miscarriages (45/390, 11%).
The referral patterns indicated that thrombophilia testing was adopted by both primary and secondary care clinicians, and encompassed both individuals who have had a DVT, and healthy individuals who have a family history of thrombophilia or DVTs.
Of the 97 individuals invited, 42 consented to interview. Twenty-five of the 42 participants reported having been referred to the test because of family history of thrombophilia or DVTs, ten were referred because of personal history of DVTs, 5 were referred for other reasons (such as miscarriages) and seven were unaware of being tested. Most of the participants (37/42) were women; 22 belonged to social class I and II, whilst 20 belonged to social class III, IV and V [48
]. Twenty-six individuals with positive results for a thrombophilia marker (participants had often been screened for a panel of five markers) responded to our invitation to participate, but we only recruited nine participants who had normal results (seven were unaware of having had the test). The slanting of the sample towards individuals with thrombophilia should be borne in mind when interpreting the findings.
One theme that emerged from the interviews was that participants did not consider thrombophilia testing special even if it identified a genetic susceptibility; we have discussed this theme elsewhere [49
]. Another prominent theme that emerged was that participants' understanding of the test, its results and implications varied widely. This article focuses on this diversity in understandings of the test, exploring processes that lead to better or worse understanding.
The understanding of the individuals did not fall into clear categories but lay on a spectrum. Some participants understood the test well; they knew they had had the test, recalled its results (including the marker they had inherited) and understood the familial and preventive consequences. Others had a fair or poor understanding of the test. Some presumed their test results were normal, even though they could not recall receiving their results. Some knew they were positive for thrombophilia but did not know which marker they had inherited even though different markers are associated with differing risks; they were also unsure about whether or not they were doing the right things to prevent DVTs. Seven participants were unaware of having had the genetic test.
The participants who understood the test well derived predominantly from social class I and II, and participants with poorer understanding were predominantly from social class III, IV and V.
Three sub themes emerged from the interviews that brought into relief the processes that led to differences in understanding: (i) the referral situation, (ii) receiving and interpreting results, and (iii) understanding of the risk and the implications of testing.
The referral situation
Individuals, who understood the test well, sometimes described the information provided by the doctors as "comprehensive" (Participant 034); other times they commented that for their general practitioner "it was actually the first time she had heard" of factor V Leiden (025). Well-informed participants, who were referred for the test based on family history of thrombophilia had often acquired a basic understanding of thrombophilia prior to testing from knowledgeable family members. When relatives had provided individuals with reasonably good information, which was complemented by the doctor's advice, their understanding of the test at referral was straightforward, as illustrated by the account of a young, well-educated woman:
Mum just said that there was a test that me and [my brother] had to have to see, if we'd got this factor V Leiden. ... And when I went in with Dr H he just told me what it was. 
Sometimes the information provided by relatives had been less clear, but participants had sought further information from the Internet prior to contacting a clinician so that they "probably knew all that [the doctor] told and more already" (021). Occasionally the participant had taken on the collection of information on behalf of the entire family, particularly in cases where the participant deemed other family members to have difficulties in accessing and understanding information. A community care worker had consulted the Internet on behalf of her family after her brother tested positive for factor V Leiden when diagnosed with a DVT, from complications of which he later died. She also noted that such information seeking was necessary in the case of thrombophilia but not in relation to well-understood and supported illnesses, such as diabetes:
We didn't know anything about it, so we sort of just looked [on the Internet], and basically we did it for everybody else, you know. Obviously, my mum and dad was concerned because of [my brother]. ... But no, I don't think [we usually consult the Internet]...even with Andrew's [partner's pseudonym] diabetes we've never gone on the Net for that. But that's totally different. A diabetic nurse is so good. We've had loads and loads of information for that. 
Less informed participants had also often been referred for testing on account of a family history of thrombophilia or DVTs, but they frequently indicated that their relatives had not provided them with much background knowledge. They were more likely than well informed participants to report that their doctor had not provided them with good information, saying, for example, that he "never explained [the test] properly" (030). Others acknowledged they had trouble understanding information, stating that it "went over our head" (023). A middle-aged male accountant had asked for the test, after his brother's doctor recommended all family members to be tested following his DVT; the brother had not told him much about the condition, and the participant ended up knowing he was positive but did not know the marker. He considered that he was provided with little information, as the doctor presumed he knew about the test as he requested it:
She [did not explain the test] in so many words because of the fact that I'd asked for a test myself ... I think that she assumed that I knew what I was being tested for. And as far as I am aware it was just a blood test that had to be done and we went from there 
Two of the participants who were unaware of having had the genetic test had most likely been referred to it in a consultation over prescribing the oral contraceptive or HRT. There had been a difference in opinion between the clinician and the patient, and the test was probably used to mediate the difference and was lost under the main issue of prescribing. Five participants who were unaware of having had the genetic test had had several DVTs or cerebrovascular events. They related that they sometimes had to "insist" on proper medical attention (for example, when experiencing an acute DVT) (026). Yet, they tended to trust their doctors the details of their complex care, such as multiple diagnostic tests, as indicated by the account of a retired pub-keeper:
I don't remember ever having had the test. ... But I have had lots of blood tests. But I've never known ... really what they were doing with it. 
Receiving and interpreting results
Participants had learnt of their genetic test results in inconsistent and sometimes informal ways: during a consultation, in writing, on the phone or they did not recall receiving the results. Less informed participants were sometimes confused about the manner in which results would be communicated to them. In several cases they had expected their doctor to call them in person, if the results were positive. In a couple of cases participants thought their results were normal or that they were "clear" because the doctor had not contacted them, only to find out later, when they queried about it, that they "had it" (023). A couple of participants did not at the time of the interview recall receiving the results, presuming they were "fine," as the doctor had not called them (011). One participant was referred to the test after recurrent miscarriages and was given "a negative result when it was positive" by the receptionist (038). Afterwards she had another miscarriage and a daughter who died soon after birth. She admitted that the cause of the tragedy was uncertain, but that in her "heart" she believed it all had to do with clotting, and that if the test results had been conveyed correctly she may have "looked at it a bit closer" during the subsequent pregnancies (038).
On many occasions the more and less informed participants had received the test results in identical manner but reacted to the information differently. After learning their results the well informed participants often sought additional information or advice from their doctors and elsewhere. This is illustrated by a university lecturer's description of her initial reaction to learning on the phone she had inherited factor V Leiden and having been reassured by her doctor not to worry:
I think I rang up for [the results] ... So, I immediately made an appointment to talk to my doctor about it. ... She looked at me and she said, "You're not obese and you're not a smoker. You don't need to worry". And I felt, "Well, don't just dismiss me" ... [One needs] advice and clarification about what things you do need to worry about and what things you don't need to worry about. I think I've sort of gleaned information by looking at the Internet or talking to my brother or talking to my father. It just makes me much more secure, really. 
A less informed participant, a young woman working in the supermarket, was also communicated the test results over the phone. Yet, rather than pursue further information she concluded that the matter was not important as her doctor had reassured her that she needed to take no specific actions consequent on the test results:
Eventually someone told me that apparently they weren't supposed to tell me like that. I was supposed to go in and see them, but they had just told me [the results] over the phone. But, mmm, I still didn't go and see the doctor. They didn't call up for me or nothing ... and my GP had said that I would just carry on as normal anyway. 
Many participants, involving both those with good and those with poor understanding, stated that they would have appreciated written information on thrombophilia and prevention, which they could reread at home. They commented that they felt they were not able to "take it all in" (036) during a consultation.
Understandings of risk and the implications of testing
In the first few interviews patients described themselves as "not too anxious" (037) or "blasé" (039) about thrombophilia. In later interviews we explored this theme systematically by asking the participants whether they considered the risk associated with thrombophilia to be small, medium, or high (this question was not posed when individuals were unaware of having had the genetic test). Of the twenty-three interviewees asked this question only three thought the risk was high, eleven estimated it as small and nine as medium. The three participants who considered their risk high all had a poorer general understanding of thrombophilia.
Most participants did not recall their doctor explaining the risk to them; they had "just figured it out" (017), concluded their risk was medium due to family history ("father had it") (010) or gleaned the understanding from "the way the doctor explained it" (018). Some participants remembered the doctor relating a numerical risk figure, such as "1 in 100" (020); one participant recalled the doctor estimating that the risk was "a lot bigger," but she did not agree with him, as she had been "healthy" (039).
We have reported elsewhere that participants, who knew they had thrombophilia, had stopped taking the combined contraceptive pill and hormone replacement therapy but had not changed their lifestyle [49
]. There were no dramatic differences in terms of preventive actions reportedly taken following communication of test results between the well and the less well-informed participants, excluding those who were unaware of being tested.
However, the participants differed in respect of the confidence in their acquired knowledge. A female scientist, who had experienced a DVT in her early thirties after going on the pill and had been identified to have inherited factor V Leiden, had requested a referral to a consultant to ask about prevention. Her knowledge was very detailed and covered all eventualities:
I often have to travel by plane to Rome. [Professor A] told me that I can, if I want to, have an injection of heparin. He said, if I feel more comfortable, I can just take half of an Aspirin. ... And obviously he tried to explain to me how I can change my life in order to help my circulation and to help myself keep fit. And then I also asked what of contraception? ... So he said that there are different alternatives. So, then I went to a clinic in Exeter, and I have a coil now, so I'm quite happy with it. Then I asked him about pregnancy as well. What should I tell to my doctors and what should I ask them to take care of? And he just said I should be on heparin, I think in the hospital .
A homemaker, who had experienced a DVT during pregnancy and been identified to have thrombophilia, was much less certain about prevention. The participant also asked the interviewer for advice on prevention:
Oh, yes [the doctor did mention hormones] I'm not allowed to go on the Pill. ... I just ... do a lot of walking ... But, apart from that, well, I don't know [what to do to prevent clotting]. I just carry on as day-to-day, and I'm pretty happy with that. ... I suppose you could tell me the most high risk factor of it all, because I don't know a lot about it to be honest. 
Most of those participants who had had DVTs but were unaware of having had the test, said they would want to know, "if it is heritable" to help their children. Some of them stated they had "suspected" (035) that abnormal clotting was a hereditary condition. However, their lack of understanding did not enable them to clarify their suspicions or to inform their children about familial risk:
Yes, [I would like to know if there is a risk in my family] especially, if it might help my offspring ... Because our elder daughter has got very big legs. She's always had very sturdy legs but they ... they could give her problems, I think, later on.