Object-oriented software systems contain large number of modules which make unit testing, integration testing, and system testing very difficult and challenging. While the aim of unit testing is to show that individual modules are working properly and the aim of the system testing is to determine whether the whole system meets its specifications, the aim of integration testing is to uncover errors in the interactions between system modules. However, it is generally impossible to test all connections between modules because of time and budget constraints. Thus, it is important to focus the testing on the connections presumed to be more error-prone. The goal of this work is to guide software testers where in a software system to focus when performing integration testing to save time and resources. This paper proposes a new approach to predict and rank error-prone connections. We use method level metrics that capture both dependencies and internal complexity of methods. We performed experiments on several Java applications and used error seeding techniques for evaluation. The experimental results showed that our approach is effective for selecting the test focus in integration testing.