Could It Be Colorectal Cancer? General Practitioners' Use of the Faecal Occult Blood Test and Decision Making – A Qualitative Study

Cecilia Högberg; Eva Samuelsson; Mikael Lilja; Eva Fhärm


BMC Fam Pract. 2015;16(153) 

In This Article


When we analysed the interviews in an effort to determine what makes GPs suspect CRC and to identify their practices in further investigations, four categories were identified. Each is described below.

Careful Listening – With Awareness of the Pitfalls

The importance of attentive listening to the patient and of taking a careful, thorough medical history was stressed, and the GP's background knowledge of the patient was taken into consideration.

The interviewees described using their basic knowledge of the manifestations of CRC to evaluate the patient's history. Symptoms that were new to the patient aroused suspicion. Rectal bleeding and changes in bowel habits were considered important factors, but vague symptoms, anaemia, and clinical findings could also elicit suspicion. Age, family history, and the patient's previous help-seeking behaviour and anxiety could influence.

(What causes you to be suspicious?) "Traces of blood in the stool could be one thing. Also, that the patient, perhaps not as specific, feels unwell or has lost weight. … Changed bowel habits of course. … Sometimes, nonspecific abdominal pain." (GP9)
"The patient feels different in some way." (GP3)

If the patient regarded his or her bowel habits to be changed, they were considered to be changed.

"It's the patient that knows how things were. … If something brings the patient to me because he or she feels that something is different, then there is in fact a change." (GP2)

However, careful listening to the patient's history carried a risk of being misled by the patient's own explanations of his or her symptoms. A history of menorrhagia with anaemia, haemorrhoids, or irritable bowel syndrome (IBS) could also be misleading. Continuity of care could be helpful but also a risk.

"Sometimes, patients have their own explanations, which may act as a kind of smokescreen. … The explanation they come up with can ultimately delay things." (GP3)
"This group of patients that are nervous and contact us very often, they live a little dangerously, because if they did develop something malignant, then there is a big risk that things would be delayed." (GP6)

With polysymptomatic patients, it could be difficult to grasp what was important to listen to:

"Middle-aged and older patients with a lot of symptoms who perhaps add, in passing, that something feels a bit different. Sorting through this plethora of symptoms, well, that can sometimes be difficult." (GP 8)

Tests Can Help - the iFOBT Can Also Complicate the Diagnosis

When investigating possible CRC, all physicians used the iFOBT and other laboratory tests. All discussed the limitations of iFOBTs, but their handling of the test results varied. Some found the iFOBT to be an important aid, while others were doubtful about its usefulness.

They all said that they initially ordered a standard battery of laboratory tests with personal variations. Anaemia was described as a significant finding that was important to investigate further.

The iFOBT results were considered to be easiest to evaluate when all three samples of a set were positive or negative. An iFOBT with three positive samples generally resulted in a referral and was thought to perhaps quicken the referral process and be helpful in prioritising at the hospital.

"If my clinical findings support me in taking things further, and I also have three positive iFOBTs, then I think this strengthens the investigation and can perhaps speed up the referral as well." (GP1)

Three negative samples could support watchful waiting. Negative iFOBTs were not thought to be conclusive, and it could be difficult to determine whether these were sufficient to exclude CRC. There were also situations when there was conflicting information from the medical history and the iFOBT results.

"But, in situations where I'm wavering, it might support the theory; I did actually have three negative iFOBTs." (GP2)
"When the iFOBTs are negative but the patient is experiencing symptoms, I still move forward with the investigation." (GP4)

When just one of three samples was positive, there was a grey area. Some regarded this as a positive test and referred the patient for bowel imaging, while others were more hesitant and sometimes repeated the test, taking another three samples. If repeated tests were negative and the patient's history seemed benign, the physician could decline to refer the patient, who was subsequently followed at the healthcare centre.

"Fact is, I always act on a positive iFOBT, even when I am convinced the symptoms are functional. I take these tests for a reason." (Registrar2)
( one of three samples positive) "Then it's more difficult. Yes, I redo it. Yes. And, if there's then a series of three negatives, well then I consider it a negative, yes. Naturally, it's also the problems, the symptoms that determine if you can, sort of, let it go." (GP6)

With a history of rectal bleeding, some often used iFOBT to confirm the bleeding, while others found this unnecessary.

"Many times, I think I've done the iFOBT to verify, to have it in the records as well, that this is really the case." (GP1)
"If there is visible blood, then I naturally don't do any iFOBTs." (GP7)

The interviewees described being generous with the use of rectoscopy; with a history of rectal bleeding it was performed as a rule. Many thought that it was difficult to decide when rectoscopy findings were sufficient to explain rectal bleeding, irrespective of the iFOBT results. With positive iFOBT results, findings of haemorrhoids were sometimes considered to be a sufficient explanation. Negative iFOBTs could sometimes reinforce the decision not to refer for bowel imaging when there was a history of rectal bleeding and findings of haemorrhoids, especially in younger patients.

"If I have positive iFOBTs, then I'd like to know why this is the case … and in those cases a rectoscopy may suffice, if I find something that's bleeding there." (Registrar1)

There were different opinions on iFOBTs' usefulness. While some found them to be of great help, others found them not especially helpful.

"Yes, they're of huge help, yes. … They're of crucial importance." (GP6)
"Yes, they serve as an indication." (GP8)
"In reality, they're not so useful. … They don't help me very much, I'm hesitant to the usefulness of iFOBT." (GP5)

To Refer or Not to Refer - Safety Margins Are Necessary

The interviewees described their efforts to make clinical judgements that were plausible, and in which they felt reasonably secure. They wanted better communication both with and within secondary care and strived to keep their patients' best interests in mind.

Uncertainty was described as a part of everyday work. Patients with recurrent and vague symptoms could be the most difficult to handle.

"I think, after all, this is my job! This is what I get paid to do, so I have to make the assessment and take responsibility for it. It's up to me to harbour the uncertainty." (GP2)
'The real difficulty, I think, is actually people with vague stomach problems, perhaps with IBS, who come to us from time to time… when have things changed so much, and when has so much time passed that it's time to move on again?" (GP2)

To handle uncertainty they thought it was helpful to discuss cases with their colleagues at the health care centre or to ask specialists in secondary care for their opinions. It could also be helpful to reflect upon things for some time before deciding upon a course. Involving the patient in the referral decision was considered to be important. Especially when there was some uncertainty, they thought it important with a dialogue and to come to a consensus with the patient, all without passing on the feeling of uncertainty.

"This is probably the hardest part. When things are vague, when to leave it. The conversation with the patient is really important in order to sense where he or she stands psychologically in all this." (GP4)

In general, the GPs considered themselves to be generous with referrals, but they also thought that the referrals should have reasonable grounds.

'The level of investigation must have a safety margin … Otherwise, we're too restricted in our investigations." (GP6)
"Most of what we investigate turns out to be nothing. … You have to draw the line somewhere and keep a cool head and wait a while." (GP7)

Once having decided to refer, the physicians had to choose between a referral for a radiological examination or an endoscopy. As resources for colonoscopy were limited, referral for this could involve advocating for their patients. Many described experiences of insufficient information from the hospital regarding which patients to refer to what department and about current (sometimes long) waiting times. They also told of their concern about increasing demands from secondary care that tests should be carried out in primary care before referral.

"Sometimes you find a haemoglobin level that is so low that you don't want to investigate things at a primary care level because you know how long it takes there, and then you send the patient to the hospital because you think they will get admitted, but they don't always." (GP3)

There were worries about colonoscopy and laxation being trying for the patients. Here, too, long distances to the hospital could be a problem. The interviewees engaged district nurses to help with laxation and travel arrangements, and sometimes they arranged for hospital care.

"In particular, many older patients would benefit from being admitted to have purging done at the hospital." (GP5)

When the decision was not to refer, the doctors described using different levels of safety netting. Time was considered an important tool.

"If you feel quite certain, you can leave it very open, for example, say something like 'get in touch if you need to'. If you feel there are uncertainties, perhaps give the patient a time frame, like 'get in touch no later than this time, or if exactly this or that happens'." (GP1)

Growing More Confident – But Also More Humble

With increasing experience, the GPs described being more confident in making decisions but also becoming more humble.

They described feeling more secure about not examining every symptom in detail, and learning to harbour uncertainty and live with the fact that nothing was certain.

"Deciding whether to investigate or not, for example. And, how to follow up. I've gotten used to it over the years, and it's not a big problem. I can make a decision pretty well and then let it go without it bothering me." (GP7)

Gut feelings were considered to be based on experience, and so they changed over time. With greater experience, it could also be easier to see whether patients diminished their problems.

"Perhaps you understand people better with time, you understand that some perhaps play down their symptoms because they're scared of what it could be, and that you somehow see through this better with time." (GP6)

The interviewees also noted that growing knowledge and experience did not always lead to greater certainty. Instead, they described becoming more cautious, with a greater awareness of the risk of pitfalls, and perhaps being more generous with referrals for bowel imaging.

"You don't always feel more confident just because you have more information. … I've become more uncertain about things like iFOBT, for example. … I used to think those tests were a lot more help than I do these days." (GP4)

The GPs described becoming less concerned about what others thought about their referral decisions and also more humble. The patients were their focus. Nevertheless, they valued dialogue with their colleagues at the hospital and wished for better communication.

"I've worked for quite a few years … there's no work prestige involved. … I don't really care if there is someone at the other end that laughs at my referral … it's not my problem." (GP9)
"I still think it would be better if I could discuss things a bit more with the hospital." (GP3)

All of the GPs recounted their personal experiences with patients that turned out to have CRC. In some cases, it had been easy to decide how to act, while delays were described in other cases. A menstruating woman with anaemia was cited as one example of a situation that resulted in a delay, and a second example was a patient who did not want to be referred.