To a non-Briton, the oft-repeated assertion that the NHS is “the envy of the world” can grate. If imitation is the sincerest form of envy, the world’s laggardly adoption of free-at-point-of-use health care is perhaps the truest mark of how much emotional investment the rest of the world really has in the UK’s health system. Early in The Life Project, her book on the British birth cohort studies, Helen Pearson describes them as “the envy of scientists all over the world”. In this case, envy is easier to precisely pinpoint; birth cohort studies have become all the epidemiological and social scientific rage in recent decades, especially around the turn of…