The problem is one of placement and perspective. The former (of) reflects situations where sociologists maintain their disciplinary base (an academic sociology department for example) and train their sociological lens on fields of inquiry (such as medicine) for the purpose of answering sociological questions.
The Gold Coast was a British colony on the Gulf of Guinea in west Africa that became the independent nation of Ghana in 1957. The first Europeans to arrive at the coast were the Portuguese in 1471.
For a time the Gold Coast formed officially a past of the West African Settlements and was virtually a dependency of Sierra Leone. In 1874 the settlements on the Gold Coast and Lagos were created as a separate crown colony, this arrangement lasted until 1886 when Lagos was itself separated from the Gold Coast administration.