Article type
Year
Abstract
Background: Real-world data derived from patient records or databases can be used to investigate treatment effects in fields where randomized controlled studies (RCTs) are difficult to conduct for ethical or other reasons. Here we present an example from an HTA report on epilepsy surgery where real-world data from observational studies were used to strengthen the certainty of evidence.
Objectives: To investigate the effect of resective epilepsy surgery compared to pharmacological treatment only through a systematic review.
Methods: A systematic review following the PRISMA guidelines was conducted. RCTs and observational studies with a comparison group were searched and assessed for eligibility and risks of bias. The population was patients with drug-resistant focal epilepsy who had been clinically assessed and selected as candidates for resective epilepsy surgery. The primary outcome was seizure freedom 1-2 years after surgery. Meta-analyses were performed separately for RCTs and observational studies, but the certainty of evidence was assessed on the basis of all studies.
Results: Three RCTs and five observational studies were included after assessment of eligibility and risks of bias. The observational data were derived from patient records, national registries, or local databases. The results from the observational studies supported the results from the RCTs but generated a somewhat larger estimate of the effect. The certainty of evidence was assessed as ‘high’ for a nonnull effect favoring resective surgery in comparison to pharmacological treatment only (GRADE ++++). Downrating in the imprecision domain was prevented by the larger study population that was provided through the observational studies.
Conclusions: Real-world data strengthened the certainty of evidence and improved the generalizability to clinical practice in this example from the field of epilepsy surgery. Despite challenges relating to controlling for confounding factors, observational studies may constitute an important input to the evidence base in areas where RCTs are scarce.
Patient or healthcare consumer involvement: This systematic review was part of a larger project in which national guidelines were developed for the diagnosis and treatment of epilepsy. Patient representatives were involved at a later stage in the guideline process.
Objectives: To investigate the effect of resective epilepsy surgery compared to pharmacological treatment only through a systematic review.
Methods: A systematic review following the PRISMA guidelines was conducted. RCTs and observational studies with a comparison group were searched and assessed for eligibility and risks of bias. The population was patients with drug-resistant focal epilepsy who had been clinically assessed and selected as candidates for resective epilepsy surgery. The primary outcome was seizure freedom 1-2 years after surgery. Meta-analyses were performed separately for RCTs and observational studies, but the certainty of evidence was assessed on the basis of all studies.
Results: Three RCTs and five observational studies were included after assessment of eligibility and risks of bias. The observational data were derived from patient records, national registries, or local databases. The results from the observational studies supported the results from the RCTs but generated a somewhat larger estimate of the effect. The certainty of evidence was assessed as ‘high’ for a nonnull effect favoring resective surgery in comparison to pharmacological treatment only (GRADE ++++). Downrating in the imprecision domain was prevented by the larger study population that was provided through the observational studies.
Conclusions: Real-world data strengthened the certainty of evidence and improved the generalizability to clinical practice in this example from the field of epilepsy surgery. Despite challenges relating to controlling for confounding factors, observational studies may constitute an important input to the evidence base in areas where RCTs are scarce.
Patient or healthcare consumer involvement: This systematic review was part of a larger project in which national guidelines were developed for the diagnosis and treatment of epilepsy. Patient representatives were involved at a later stage in the guideline process.