Natsuki used meta analysis

as her data collection tool because her hypothesis concerned international issues and it would have been difficult to make a direct observation because the subjects of the hypothesis were not necessarily directly attainable. Through meta analysis, she was able to compare Japan's and Sweden's approaches to achieving gender equality in detail. 

Overall, the effectiveness of

the meta analysis was satisfactory given the circumstances. Evidently, it would have been more satisfactory if Natsuki had the option of interviewing or observing the subjects of her hypothesis.