However, all the above studies were performed prior to the discovery of further defining sub-haplogroups within R1a1.
The above studies by Levitsky et al., were an important precedent for this work.
If a survey includes the milder types, as the above study did, the prevalence will be much higher.
First- it should be noted that the above study is a review article.
The above study does not meet either of these criteria.
The above mentioned study is inherently flawed due to the lack of a control group.
In opposition to the above studies are those which have been carried out by anthropologists, who have applied traditions more central to that discipline.
The above studies showed that depth was a continuous variable correlating with prognosis.
However, many researchers have debated the results of the above studies.
In the above study, most victims presented with about three medical problems in some combination out of 103 different reported symptoms.