A screening questionnaire for generalized tonic-clonic seizures: Hospital-based validation vs field-validation method

Area of Science:

• Neurology
• Epidemiology
• Medical Diagnostics

Background:

• Epilepsy screening tools are often validated in hospitals, which may not reflect real-world community settings.
• A previously developed tool for detecting generalized tonic-clonic seizures (GTCS) was validated in rural Bolivia.
• The accuracy of this tool may differ between field and hospital validation contexts.

Purpose of the Study:

• To perform a hospital-based validation of a screening tool for GTCS.
• To compare the accuracy of the tool when validated in a hospital versus a field setting.
• To assess potential overestimation of sensitivity in hospital-based validations.

Main Methods:

• A hospital-based validation study was conducted at Hospital Hernandez Vera, Santa Cruz, Bolivia.
• Patients with epilepsy experiencing GTCS and control individuals were enrolled.
• Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for the screening tool.

Main Results:

• 120 questionnaires were administered to 59 patients and 61 controls.
• The screening tool achieved 100% accuracy in the hospital-based validation.
• Sensitivity (100% vs. 76.3%) and PPV (100% vs. 69.0%) were significantly higher in the hospital validation compared to previous field validation.

Conclusions:

• Hospital-based validation of the GTCS screening tool yielded 100% accuracy.
• The study confirms that hospital-based validation can lead to an overestimation of sensitivity compared to field validation.
• This highlights the importance of context in validating diagnostic screening tools for epilepsy.