The study findings were limited by several factors including the use of an ecologic study
design, which was chosen to help reduce selection bias, but that did not show evidence of the field effectiveness of the PCVI3 vaccine.
"These results require confirmation in other populations, given known methodological limitations of ecologic study
Among study limitations, our ecologic study
design could not distinguish between long-term trends or behavioral factors and vaccine effects.
(5) In an ecologic study
on healthy adults in Iran, serum selenium concentrations did not differ in males (124 [micro]g/L) and females (116 [micro]g/L) (P=0.49).
Vulvar carcinoma has a low prevalence and is usually symptomatic (SOR: B, ecologic study
and a case series).
Our analyses suggest that an ecologic study
on lung cancer and radon exposure in BC might reach divergent conclusions depending on whether the radon potential map or the radon observations were used for exposure assessment.
An ecologic study
was conducted using records of new orofacial cleft cases during the period from 1998 to 2002, in the regions and state capitals of Brazil, by consulting the Public Health Hospital Information System (SIH-SUS), which is administered by the Ministry of Health, and processed by Datasus (15) (Department of Information Technology of the National Health System), according to sex, geographic region and state capital.
Streptococcal resistance is directly associated with antibiotic use, a multinational ecologic study
Hillier and her associates also conducted an ecologic study
of 2,110 individuals, which showed no correlation between hip fracture among residents of areas with highly fluoridated water and those living elsewhere.
An ecologic study
design was used to examine the association between risk factors and outcome on groups rather than individuals.
(3) study utilized TABULAR DATA OMITTED the ecologic study
design to investigate the relationship between exposure to air emissions produced by the petroleum and chemical industries and average annual cancer incidence among residents of Contra Costa County.
During the ecologic study
, 126 rodents were captured: 68 (53.9%) commensal synanthropic species, 49 (38.8%) wild rodents [Calomys callidus (n = 46), Proechimys sp.