New Zealand into 285 distinct regions. According to Statistics New Zealand the classification of wards is “designed to allow for the recognition of communities within a district and to increase community involvement in the local government system [34].” Based on the building damage ratio calculations from the Canterbury Earthquake Recovery Authority (CERA), we grouped together the six wards that form Central Christchurch based on thePLOS ONE | DOI:10.1371/journal.pone.0124278 May 1,3 /Regional Differences in Psychological RecoveryFig 1. Map of the Christchurch region showing different wards and the different damaged-grouped regions. The most damaged wards were those in the North East (Shirley-Papanui and Burwood-Pegasus) followed by the moderately-damaged wards of Spreydon-Heathcote and Hagley-Ferrymead in the South-East, and the least-damaged wards of Fendalton-Waimairi and Riccarton-Wigram in the West. Note. Map was generated using http://www. openstreetmap.org.nz/. doi:10.1371/journal.pone.0124278.gamount of relative damage suffered in the given ward [27, 28]. The most damaged (n = 80) were the Shirley-Papanui and Burwood-Pegasus wards, the moderately damaged (n = 91) were the Spreydon-Heathcote and Hagley-Ferrymead wards, and the least-damaged (n = 96) were the Fendalton-Waimairi and Riccarton-Wigram wards. The geographic boundaries for these wards are presented in Fig 1.Sampling procedure and retention ratesTo provide a general overview of sample retention in Christchurch, initially (i.e., in 2009), we sampled between 80?00 people from each of the six wards that comprise central Christchurch (575 people in total), and retained between 51?6 purchase STI-571 participants from each of these wards in 2010 (i.e., the first wave of the study to include measures of psychological distress). The total retention rate from the pre-Earthquake 2009 wave in 2010 was 61.39 . As with the overall NZAVS, we had a gender bias, with women (n = 337) being more likely to respond than men (n = 238). In total, by 2012, we retained 267 participants (172 women, 95 men), who had provided age and gender and who completed the K6 in all three of these waves (a 75.64 retention rate from 2010). Research on the entire NZAVS over four time points has shown that men were more difficult to retain [35].PLOS ONE | DOI:10.1371/journal.pone.0124278 May 1,4 /Regional Differences in Psychological RecoveryTable 1. Items of the Kessler-6 (K6) Non-Specific Psychological Distress Scales, scored on a 0 (none of the time) to 4 (all of the time) scale. During the last 30 days, how often did. . . . . . you feel nervous . . . you feel hopeless? . . . you feel restless or get WP1066 fidgety? . . . you feel so depressed that nothing could cheer you up? . . . you feel that everything was an effort? . . . you feel worthless? doi:10.1371/journal.pone.0124278.tCritically, chi-square tests indicated that there were no differences in retention rate across the regions of focus from the initial sample in 2009 to 2010 (2(2,575) = 3.53, p = .171). However, there were differences in retention rate across regions from 2009 to 2011 (the first time point after the second earthquake; 2(2, 575) = 8.36, p = .015), as the most damaged regions had a slightly lower retention rate (52.7 ) than did the moderately damaged (61.3 ) and least damaged (67 ) regions. There were no differences in retention from 2009 to 2012 (2(2,575) = 5.03, p = .081). Furthermore, there were no differences in 2010 K6 scores between those who were retaine.New Zealand into 285 distinct regions. According to Statistics New Zealand the classification of wards is “designed to allow for the recognition of communities within a district and to increase community involvement in the local government system [34].” Based on the building damage ratio calculations from the Canterbury Earthquake Recovery Authority (CERA), we grouped together the six wards that form Central Christchurch based on thePLOS ONE | DOI:10.1371/journal.pone.0124278 May 1,3 /Regional Differences in Psychological RecoveryFig 1. Map of the Christchurch region showing different wards and the different damaged-grouped regions. The most damaged wards were those in the North East (Shirley-Papanui and Burwood-Pegasus) followed by the moderately-damaged wards of Spreydon-Heathcote and Hagley-Ferrymead in the South-East, and the least-damaged wards of Fendalton-Waimairi and Riccarton-Wigram in the West. Note. Map was generated using http://www. openstreetmap.org.nz/. doi:10.1371/journal.pone.0124278.gamount of relative damage suffered in the given ward [27, 28]. The most damaged (n = 80) were the Shirley-Papanui and Burwood-Pegasus wards, the moderately damaged (n = 91) were the Spreydon-Heathcote and Hagley-Ferrymead wards, and the least-damaged (n = 96) were the Fendalton-Waimairi and Riccarton-Wigram wards. The geographic boundaries for these wards are presented in Fig 1.Sampling procedure and retention ratesTo provide a general overview of sample retention in Christchurch, initially (i.e., in 2009), we sampled between 80?00 people from each of the six wards that comprise central Christchurch (575 people in total), and retained between 51?6 participants from each of these wards in 2010 (i.e., the first wave of the study to include measures of psychological distress). The total retention rate from the pre-Earthquake 2009 wave in 2010 was 61.39 . As with the overall NZAVS, we had a gender bias, with women (n = 337) being more likely to respond than men (n = 238). In total, by 2012, we retained 267 participants (172 women, 95 men), who had provided age and gender and who completed the K6 in all three of these waves (a 75.64 retention rate from 2010). Research on the entire NZAVS over four time points has shown that men were more difficult to retain [35].PLOS ONE | DOI:10.1371/journal.pone.0124278 May 1,4 /Regional Differences in Psychological RecoveryTable 1. Items of the Kessler-6 (K6) Non-Specific Psychological Distress Scales, scored on a 0 (none of the time) to 4 (all of the time) scale. During the last 30 days, how often did. . . . . . you feel nervous . . . you feel hopeless? . . . you feel restless or fidgety? . . . you feel so depressed that nothing could cheer you up? . . . you feel that everything was an effort? . . . you feel worthless? doi:10.1371/journal.pone.0124278.tCritically, chi-square tests indicated that there were no differences in retention rate across the regions of focus from the initial sample in 2009 to 2010 (2(2,575) = 3.53, p = .171). However, there were differences in retention rate across regions from 2009 to 2011 (the first time point after the second earthquake; 2(2, 575) = 8.36, p = .015), as the most damaged regions had a slightly lower retention rate (52.7 ) than did the moderately damaged (61.3 ) and least damaged (67 ) regions. There were no differences in retention from 2009 to 2012 (2(2,575) = 5.03, p = .081). Furthermore, there were no differences in 2010 K6 scores between those who were retaine.