IS PEFR reliable to measure pulmonary function?

hey i am a final year student doing a project in which i have to measure improvement in pulmonary function in women with forward shoulder posture, i would like to know if PEFR and FVC are enough to measure pulmonary function

first you have to know whether the women included in your study have already lung impairment or not. simply PEFR and FVC are not enough to measure. also take FEV1, FEV1/FVC AND FEF25-75%. most important thing is that when performing FVC maneuver the forceful expiratory time must be 6 seconds....