Validating an instrument
With over 5,000 installations – in 50 countries worldwide – there’s bound to be one close by!
Validation services can help you save both time and money by streamlining your validation procedures.Once the researcher is certain no other instruments exist, the researcher should review the literature to determine the operational definitions of the constructs that are to be measured.This can be an arduous task because operationalizing a variable does not automatically indicate good measurement and therefore the researcher must review multiple literatures to determine an accurate and meaningful construct.Objective To prospectively validate the HERDOO2 rule (Hyperpigmentation, Edema, or Redness in either leg; D-dimer level ≥250 μg/L; Obesity with body mass index ≥30; or Older age, ≥65 years), which states that women with none or one of the criteria can safely discontinue anticoagulants after short term treatment. Setting 44 secondary or tertiary care centres in seven countries.Participants Of 3155 consecutive eligible participants with a first unprovoked venous thromboembolism (VTE, proximal leg deep vein thrombosis or pulmonary embolism) who completed 5-12 months of short term anticoagulant treatment, 370 declined to participate, leaving 2785 enrolled participants. Interventions Women with none or one of the HERDOO2 criteria were classified as at low risk of recurrent VTE and discontinued anticoagulants (intervention arm), whereas anticoagulant management for high risk women (≥2 HERDOO2 criteria) and men was left to the discretion of the clinicians and patients (observation arm).