Africans are among the most likely of the world's citizens to be forced to pay bribes - but they are also the most confident that their governments are trying to stop the practice, according to a new study.

The study - the only world-wide public opinion survey on people's experiences with corruption - was published on Wednesday by the anti-graft coalition, Transparency International. The survey covered 69 countries, ten of them in Africa: Cameroon, Ghana, Kenya, Liberia, Morocco, Nigeria, Senegal, Sierra Leone, Uganda and Zambia.

Of the eight countries in the survey most plagued by what TI called "petty bribery," four were in Africa. In Liberia, 87 percent of respondents reported that they or someone in their household had paid a bribe in the last year. In Sierra Leone the figure was 62 percent and in Cameroon and Uganda it was 55 percent. The lowest figure among African countries reporting petty bribery was in Nigeria, where 17 percent reported a bribe in the past year.

Nigerian respondents also reported the most confidence in their government's fight against corruption - 71 percent believed it to be effective. In Sierra Leone, 64 percent took the same view of their government, while in Ghana the figure was 58 percent and in Liberia and Uganda it was 48 percent.

In Cameroon, however, only a third of respondents expressed confidence in their government's response to corruption, while Senegal fared worst among the African countries surveyed - 16 percent thought the authorities were effective.

The study also surveyed perceptions of corruption among different categories of institutions. It found that Nigerians thought political parties were the most corrupt institutions in their society, while Liberians identified the judiciary as the most corrupt. So did Sierra Leoneans and Ugandans, but they gave the same poor ranking to public officials and civil servants.

Across the board, public officials enjoyed the least confidence among Africans surveyed: apart from Sierra Leoneans and Ugandans, respondents from Ghana, Kenya, Morocco, Senegal and Zambia rated the civil service as the most corrupt institution in their society.

The media, business and legislatures fared better in public opinion - in no participating African country were they identified as the most corrupt institution. Of all institutions, the private sector and the media scored best in the survey.

In another finding affecting business, the study found that many Africans would be prepared to pay higher prices to buy goods from corruption-free companies. Respondents from Cameroon, Ghana, Liberia, Morocco, Senegal, Sierra Leone, Uganda and Zambia were among those most enthusiastic to deal with honest businesses.

"The message to the private sector from consumers is clear," said Transparency International. "Being clean pays off. Not only does clean business create a level playing field while supporting long-term growth and productivity, it attracts customers."

The study was carried out between October 2008 and March 2009.

Transparency International says the respondents comprise a representative sample of each country's population of 16 and older.

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