In their conclusions, the researchers write that there was evidence that some files were manipulated or destroyed, many cases were not brought to justice, and that sometimes abuse suspects - primarily priests - were simply moved to other dioceses without the congregations being informed about their past.
The aim of the study is to shed light on "this dark side of our Church, for the sake of those affected, but also for us ourselves to see the errors and to do everything to prevent them from being repeated".
Earlier today, Francis met in Rome with leaders of the American Catholic Church on the issue of sexual abuse among their own ranks.
About one in six of cases documented involved rape and three quarters of the victims were abused in a church or through a pastoral relationship with the abuser.
The document, commissioned by the German Bishops' Conference, revealed that 1,670 clerics and priests had sexually abused 3,677 minors, mostly males, in the country between 1946 and 2014, news magazine Der Spiegel said.
Predator priests were often transferred to another location, but information on their criminal history were not provided to the new site. It presents the results of an investigation spanning all 27 German dioceses.
The study, commissioned by the German Bishops' Conference, was due to be presented officially on September 25, but several local media published key conclusions, including the damning finding that more than 3,600 children were sexually assaulted by priests in Germany over almost seven decades.
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She urged the Mnangagwa administration to "learn from its predecessor's mistakes" and act urgently before more lives are lost. A total of 4,000 people died and at least 100,000 people fell ill.
"I stress that the study is a measure that we owe not only to the Church but first and foremost, to those affected".
Speaking on behalf of the Conference, Bishop Ackermann said that, while he regretted that the study had been leaked, he was convinced its survey were comprehensive and thorough.
In 2010, the German church was roiled by a sex abuse scandal triggered by the head of a Jesuit school in Berlin who went public about decades-long sexual abuse of high school students by clergy.
Deutsche Welle reported that church authorities pursued only one-third of alleged abusers.
But elsewhere on Wednesday, Pope Francis summoned Catholic bishops to the Vatican for a discussion on how to protect children in February next year. Last month, an investigation in the United States found that more than 1,000 children had been abused by about 300 priests in Pennsylvania alone.
Cardinal Daniel DiNardo, president of the US Bishops' Conference, asked for the meeting after Archbishop Vigano last month accused the Pope of knowing for years about sexual misconduct by former US cardinal Theodore McCarrick and doing nothing about it.