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We commend Mullen et al 1 for their recent article in CHEST (February 2014) on quality of life and parental adjustment in pediatric pulmonary hypertension. It is indeed a very valuable research question that the authors have made an attempt to answer. However, we would like to point out a number of methodologic concerns that we fear might limit the validity of the study results. The small sample size (N 5 47) is likely to lower the statistical power of the study design. We are of the opinion that a generic scale like the Pediatric Quality of Life Inventory (PedsQL), Parent Report version, is not ideal for measurement of quality of life of the study population. A more disease-specifi c instrument such as the Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) scale, which was designed specifi cally for patients with pulmonary arterial hypertension and is primarily a patient report version, would have better suited the study purpose. 2 Lack of adjustment for multiple comparisons and lack of generalizability of the single-site study pose further questions as to the validity of the study results. We would also like to point out that the assessment of psychiatric morbidity in children with pediatric pulmonary hypertension and inclusion of psychologic morbidity detected as a factor infl uencing both patient quality of life and parental stress would have been appropriate, considering the high psychiatric morbidity demonstrated in earlier studies of patients with pulmonary arterial hypertension. 3 Not assessing and including the same (psychiatric morbidity in patients) as a confounding variable results in a lacuna that cannot be fi lled. We would recommend similar studies on a larger scale (preferably multisite) that would take into account the various methodologic challenges to shed more light on this valuable research question.