OBJECTIVE: To evaluate evidence of the capacity for causal inference in studies of associations between parental and offspring alcohol consumption in the general population.
METHODS: A systematic search for, and narrative analysis of, prospective cohort studies of the consequences of drinking, except where assessed prenatally only, or with clinically derived instruments. Primary outcome measures were alcohol use or related problems in offspring, which were collected at least 3 years after exposure measures of parental drinking. The systematic review included 21 studies comprising 26,354 families or parent-child dyads with quantitative effect measures available for each study. Criteria for capacity of causal inference included (1) theory-driven approach and analysis; (2) analytical rigour; and (3) minimization of sources of bias.
RESULTS: Four of the 21 included studies filled several, but not all, criteria and were assessed to have some capacity for causal inference. These four studies found some evidence that parental drinking predicted drinking behaviour in adolescent offspring. The remaining 17 studies had little or no such capacity.
CONCLUSIONS: There is a fairly large and consistent literature demonstrating that more parental drinking is associated with more drinking in offspring. Despite this, existing evidence is insufficient to warrant causal inferences at this stage.

BACKGROUND: A possible etiological association between endometriosis and ovarian cancer has been repeatedly reported in the literature.
OBJECTIVE: Our aim was to evaluate published epidemiological data on this issue.
METHODS: We conducted an extensive search of the literature in MEDLINE, of articles ever published until February 2014, using the key-words \"endometriosis\" and \"ovarian\" and one of the following terms in the title: \"cancer\" or \"malignancy\" or \"malignant\" or \"tumor\" or \"neoplasia\" or \"neoplasm\" or \"transformation.\" Retrieved papers were checked for further relevant publications.
RESULTS: Overall, our search yielded 1 prospective cohort study, 10 retrospective cohort, and 5 case-control studies. A meta-analysis of these studies was not considered to be appropriate, due to differences in data reporting, study design, and adjustment for confounding factors.
CONCLUSIONS: The main limitation of studies found, with one exception, was the lack of operative confirmation of endometriosis.
CONCLUSIONS: An association of endometriosis with clear-cell and endometrioid ovarian cancer was a consistent finding in most studies. On the other hand, existing epidemiological evidence linking endometriosis with ovarian cancer is insufficient to change current clinical practice. Prospective cohort studies, with prior laparoscopic confirmation, localization, and staging of endometriosis are needed, in order to further clarify this issue.