In this letter the robustness of the first results from the KamLAND reactor neutrino experiment with respect to variations in the statistical analysis is considered. It is shown that an event-by-event based likelhood analysis provides a more powerful tool to extract information from the currently available data sample than a least-squares method based on energy binned data. Furthermore, a frequentist analysis of KamLAND data is performed. Confidence regions with correct coverage in the plane of

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... the oscillation parameters are calculated by means of a Monte Carlo simulation. I find that the results of the usually adopted χ^2-cut approximation are in reasonable agreement with the exact confidence regions, however, quantitative differences are detected. Finally, although the current data is consistent with an energy independent flux suppression, a ∼ 2σ indication in favour of oscillations can be stated, implying quantum mechanical interference over distances of the order of 200 km.