The National Institute of Health and Clinical Excellence (NICE) has published new guidance for the month of January 2012. This month there is one clinical guideline and two technology appraisals that impact upon primary care.
The updated Epilepsy clinical guideline now includes several newer anti-epileptic drugs that have been introduced since the original guideline. New recommendations include:
- Basing therapeutic choice on the presenting epilepsy syndrome or presenting seizure type(s) where the syndrome type is unclear.
- Advising women and girls of the possible risk of malformation and neuro-developmental impairment in an unborn child when sodium valproate is used.
- Only prescribe buccal midazolam or rectal diazepam for use in the community for individuals who have had a previous episode of prolonged or serial convulsive seizures.
Roflumilast has been reviewed in a technology appraisal for the management of severe chronic obstructive pulmonary disease. The drug is only recommended as part of a research study (clinical trial) that is investigating using roflumilast at the same time as a bronchodilator.
Apixaban has also been reviewed in a technology appraisal for the prevention of venous thromboembolism after total hip or knee replacement in adults. The treatment has been recommended as an option based on greater efficacy and lower acquisition costs than some alternatives. Primary care may be asked to issue treatment completions.
Action: Clinicians should be aware of this new guidance and implement any necessary changes to practice.
There are many terms used to describe the design of clinical trials. There are efforts to reduce inadequate reporting in clinical trial reports and increase transparency thus aiding interpretation, for example the CONSORT Group. Some of the terms used are as follows.
Study design:
- Superiority study - aims to demonstrate that one treatment is better than another active treatment or a placebo.
- Non-inferiority study - aims to demonstrate that one treatment is not worse than another active treatment within a defined acceptable level of clinical inferiority.
- Equivalence study - aims to demonstrate that two interventions are equivalent to each other within a defined acceptable level of clinical difference.
Study methodology:
- Observational - the study watches what happens rather than directly offering interventions.
- Experimental - the study actively provides an intervention, typically this is a randomised controlled trial.
- Randomisation - participants in the study are randomly assigned to treatment groups rather than being selected. This helps to reduce selection bias.
- Retrospective - looks at events that have already happened. This method usually employs healthcare system databases.
- Prospective - looks at what happens to patient populations as time passes.
Level of 'Blinding':
- Open - participants, the clinicians conducting the study and the study assessors all know which intervention group a patient is in.
- Single blind - the participants don't know which intervention group (treatment or placebo) they are in.
- Double blind - neither the participants nor the clinicians conducting the study know which intervention group individual patients are in.
- Triple Blind - neither the participants, the clinicians conducting the study nor the study assessors know which intervention group individual patients are in.
Action: A better understanding of these terms will allow clinicians to interpret the relevance and impact of clinical studies.