Development and validation of a Frusemide Card to guide self-titration of oral frusemide in the outpatient setting
S Hussin, N A Juhari, W Y H W Isa, N M Yaacob, Z YusofAbstract
Background
Heart failure (HF) is associated with significant morbidity and recurrent hospitalisations, frequently due to fluid congestion. Although individualised diuretic adjustment is essential, structured patient-friendly tools to support safe self-titration remain limited.
Purpose
This study aimed to develop and validate a Frusemide Card to facilitate outpatient dose adjustment.
Methods
A mixed-method, cross-sectional study was conducted in two phases. In Phase 1, the card and accompanying patient leaflet were developed through systematic content construction and graphic design. Phase 2 involved content and face validation. Four domains were evaluated: (1) body weight change relative to dry weight, (2) systolic blood pressure, (3) morning frusemide dose adjustment, and (4) patient instruction leaflet. Content validity across four domains (relevance, clarity, essentiality, and patient instructions) was assessed by six experts using the Content Validity Index (CVI) and Content Validity Ratio (CVR). Relevance and clarity were rated on a 4-point scale, and essentiality on a 3-point scale. Face validation was performed with 10 HF patients, who assessed clarity and comprehension. The Face Validity Index (FVI) was calculated to determine overall acceptance.
Results
The Frusemide Card prototype was developed as a laminated, stepwise dosing table with an accompanying instruction leaflet. All content validity domains demonstrated perfect agreement for relevance and essentiality (I-CVI and CVR = 1.00; S-CVI/UA = 1.00). For clarity, domains 2–4 met acceptable thresholds (I-CVI ≥ 0.83), whereas domain 1 scored lower (I-CVI = 0.50), resulting in an overall S-CVI/UA of 0.25. However, average clarity remained acceptable (S-CVI/Ave = 0.79). Face validation showed good clarity and comprehension (S-FVI/Ave = 0.90) but low universal agreement (S-FVI/UA = 0.25). Following revision, a second patient cohort confirmed excellent clarity and acceptance, with all domains achieving perfect validity (I-FVI and S-FVI = 1.00).
Conclusions
The Frusemide Card demonstrated strong content and face validity and may serve as a practical tool to support safe outpatient self-titration of oral frusemide in HF management. Its implementation has the potential to enhance patient autonomy, optimise congestion management, and reduce healthcare utilisation. Future studies are required to evaluate its impact on clinical outcomes.