How research addresses what we don't know 

There are many questions about health, illness and the effects of treatment that we currently don't have clear answers for. Knowing what the questions are makes it easier to say what future research studies should look at.

For example, there's no medical consensus about the best treatment for an enlarged prostate gland in men (also known as benign prostatic hyperplasia, or BPH). The enlargement causes urinary problems.

BPH can be treated with lifestyle changes, medicines or surgery, or by simply keeping an eye on things (known as watchful waiting). There's no convincing evidence that one type of treatment is better than the other, and it may be a matter of personal choice by the doctor or patient, depending on what symptoms the condition causes.

Research is important to try to understand which treatment may work best, and when.

The right research project

There's benefit in repeating research if uncertainties remain. However, if the answer is already known, it will be more important to move on and ask another research question.

Doctors and researchers – and, increasingly, patients and the public – review research that's been carried out and try to choose research projects that look at important unanswered questions.

Research ethics committees now ask researchers and others seeking approval for new trials to show that they have already reviewed previous research systematically (systematic reviews). Without doing this, and consulting patients and other users of research, researchers are less likely to address questions that are relevant to patients.

Collecting together what is unknown

For centuries, researchers and scientists have made huge efforts to collect together what they know in medical libraries and, more recently, in electronic databases.

Now, researchers are collecting what they're not sure about in the UK Database of Uncertainties about the Effects of Treatments (UK DUETs).

The main aim of DUETs is to help people decide which of the unanswered questions are most important, such as how prostate cancer should be managed.

DUETs identifies the need for future research using guidelines from the National Institute for Health and Care Excellence (NICE) and other publications that highlight gaps in our knowledge.

Researchers also have increasing interest in the questions that matter to people who are ill, their families, and those who care for them. The James Lind Alliance helps patients and medical professionals decide which uncertainties should be prioritised for further research.

Managing prostate cancer

There are uncertainties about whether it's a good idea to diagnose prostate cancer early. This is because the disease is often so slow-moving that it doesn't become a life-threatening condition.

There are also uncertainties about how best to investigate men who may have prostate cancer and how to treat them. Only good research can address and reduce these uncertainties.

Read more about prostate cancer screening.

Page last reviewed: 05/01/2015

Next review due: 05/01/2017