We thank Dr Hardie for his suggestion to expand the analyses we presented in our article in CHEST1 to test the hypothesis that people with FVC < the lower limit of normal (LLN) but without true restriction (total lung capacity [TLC] > LLN) do not have an increased risk of death. Indeed, compared with people with normal TLC and normal FVC, those with a reduced FVC (but normal TLC) do not have an increased risk of death (mortality rate ratio, 0.86; 95% CI, 0.12-3.66). People with decreased TLC and normal FVC, on the contrary, have a sixfold increased mortality risk (mortality rate ratio, 6.68; 95% CI, 2.36-19.4). Compared with patients with FVC < LLN and TLC ≥ LLN, those with FVC < LLN and TLC < LLN had a mortality rate ratio of 7.78 (95% CI, 1.9-56.67). Although the estimates may not be completely reliable because of the small number of events (only two deaths in the group with TLC > LLN and FVC < LLN), these results seem to support the hypothesis that the association between reduced FVC and mortality repeatedly reported in the literature is supported by the association between TLC and mortality.