Although PRT detected dry eye in 62% as compared to 64% by Schirmer, it is more efficient in detecting severe dry eye (18%) as compared to Schirmer (14%). PRT detected dry eye in 20% patients having else detected normal/borderline by Schirmer, while Schirmer test detected 18% as dry eye having detected normal/borderline by PRT. So, PRT is almost comparable with Schirmer test, and in addition, it has many advantages as compared to Schirmer. PRT is simpler and more comfortable to the patient and can also be done in children. It causes less reflex tearing. Most important is the lesser time consumed (15 seconds) in comparison to Schirmer (5 minutes). The Kappa value between PRT and Schirmer was found to be 0.96 in this study and shows a strong agreement between the two, and also, P < 0.
05 showed that the agreement is statistically significant. So, PRT can be considered as good as Schirmer test in detecting dry eye. Footnotes Source of Support: Nil. Conflict of Interest: None declared.
The forced vital capacity (FVC) maneuver is necessary for evaluating patients with obstructive airway disease.[1,2] The American Thoracic Society and the European Respiratory Society (ATS/ERS) had standardized the FVC maneuver.[3] For each subject, the maximum FVC of three acceptable and reproducible maneuvers is used to derive spirometric indices. The FVC maneuver is usually performed in conjunction with the assessment of the timed forced expiratory volumes (FEVx). The FEVx is the volume exhaled during the first x seconds of a forced expiratory maneuver started from the level of total lung capacity.
The commonly used forced expiratory volumes are FEV1, FEV3 and FEV6. FEV/FVC percentage is by far the most frequently used index for assessing airway obstruction, bronchoconstriction or bronchodilatation.[1,3] In patients with advanced obstructive lung disease, expiration may last for a relatively long time, until the end-of-test standards for FVC are satisfied.[3,4] This may be difficult for both the patient and the technician.[5,6] Previous data showed that FEV3 and FEV6 behave like FVC in assessing ventilatory functions of the lungs.[7�C9] However, other studies concluded that complete expirations are essential for accurate measurement of the FVC-dependent spirometric indices.[10�C13] The National Lung Health Education Program recommended FEV6 as a surrogate for FVC[14]; however, few years later, some studies were against the use of FEV6 in place of FVC.
[11�C13] This controversy could partly be explained by the fact that previous studied examined Brefeldin_A patients with different pathologies.[7�C12] Studies on FEV3 and FEV6 were usually on patients with chronic obstructive lung diseases, smokers or obstructive lung diseases in general without special concern to bronchial asthma.