{'fraction_non_alphanumeric': 0.04473438956197577, 'fraction_numerical': 0.03727865796831314, 'mean_word_length': 4.805405405405406, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Geographic Origin of Publications in Major Spine Journals.

Aim of the present study was to assess the contribution of each country in the field of spine surgery. Three major spine journals were included in our study and the search conducted in PubMed for a 5-year period (2007-2012). Publications on spine surgery were assessed according to the country. A total of 6312 articles were identified and 5842 were included. Fifteen countries generated 86.9% of publications, with 31.7% by the United States, followed by Japan (9.6%), China (8.1%) and Canada (5.2%). After correction for population size Switzerland (19 studies per 106 inhabitants), the Netherlands (10), Sweden (9), Canada (9) and Australia (6) ranked the top. The USA was placed 7th after correction for population size. Small European countries with modest research funding and non-native English speaking population are more productive in relation to their population size, despite the fact that the contribution of USA is the greatest in the field of the major peer-reviewed indexed spine surgery journals.