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SSOCS 2006 was conducted as a mail survey with telephone follow-up. Four months before the onset of data collection, NCES began working with the school districts of sample schools that required prior approval to participate in the survey. On March 10, 2006, advance letters were sent to school administrators of sample schools that included the date of the first questionnaire mailing and a toll-free number to call with any questions. On March 17, 2006, questionnaires were sent via FedEx directly to the principals of the sample schools, with a cover letter describing the importance of the survey and a promotional SSOCS pen. Upon distribution of the SSOCS questionnaire to schools, letters were mailed to chief state school officers and superintendents to inform them that schools within their states and districts, respectively, had been selected for SSOCS:2006. The letters included information about the survey and were accompanied by a promotional SSOCS pen, an informational copy of the questionnaire, and the SSOCS brochure. The letters were not designed to request permission from these officials to participate in the survey, but rather as a vehicle to enhance participation. During the two weeks following the first questionnaire mailing, a screener telephone operation was conducted to verify that sample schools had received the questionnaire and were, in fact, eligible to participate. One week after the screener ended, a reminder telephone operation began, which was conducted in two 1-week phases. The primary objective of the reminder operation was to follow up with the principal or school contact to determine the status of the questionnaire. However, during the second week, the interviewer could complete the SSOCS interview over the phone at the respondent's request. Data collection ended on May 26, 2006. Returned questionnaires were examined for quality and completeness using both manual and computerized edits. If a questionnaire did not meet predetermined levels of completeness, the respondent was contacted again to resolve issues related to the missing data, irrespective of whether the items missing data were considered "critical." The criteria used to determine completeness are detailed in section 3.1 of the School Survey on Crime and Safety: 2005-2006 Data File User's Manual (Bauer et al. 2007). If a satisfactory resolution could not be reached, imputation was used to resolve data quality issues for questionnaires in which at least 60 percent of all items, 80 percent of critical items, 60 percent of item 16, and 60 percent of item 22 had been completed. Questionnaires that did not meet the imputation criteria were considered incomplete and were excluded from the analyses in this report.

2006年学校犯罪与安全调查（School Survey on Crime and Safety，简称SSOCS 2006）以邮寄调查配合电话跟进的方式实施。在数据采集启动前四个月，美国国家教育统计中心（National Center for Education Statistics，NCES）便开始与需事先获批方可参与本次调查的抽样学校所属学区开展对接工作。2006年3月10日，研究团队向抽样学校的校方管理人员寄送预通知函，其中列明了首轮问卷的邮寄日期，并提供了一条免费热线以解答各类疑问。2006年3月17日，研究团队通过联邦快递（FedEx）将问卷直接寄送至抽样学校校长手中，随附一封说明调查重要性的附函，以及一支印有SSOCS标识的宣传笔。在向各学校发放SSOCS问卷后，研究团队分别致函各州首席学校官员与学区总监，告知其各自辖区内的学校已被选中参与SSOCS 2006调查；随函附寄的材料包括调查说明、问卷样册与SSOCS宣传手册，该函件并非用于向上述官员征求参与许可，而是作为提升调查参与率的宣传载体。首轮问卷邮寄后的两周内，研究团队开展了筛选电话核查工作，以确认抽样学校已收到问卷且确实具备参与资格。筛选工作结束一周后，跟进电话提醒工作启动，该工作分为两个为期一周的阶段开展。本次跟进工作的核心目标是联系校长或学校对接人，确认问卷的回收进度；不过在第二阶段，若受访者提出要求，访员可通过电话直接完成SSOCS访谈。数据收集工作于2006年5月26日正式结束。回收的问卷通过人工与计算机化编辑相结合的方式开展质量与完整性审核。若某份问卷未达到预设的完整性标准，研究团队将再次联系受访者以解决缺失数据相关问题，无论缺失数据的项目是否被认定为"关键项"。用于判定完整性的具体标准详见《2005-2006年学校犯罪与安全调查数据文件用户手册》（Bauer等人，2007）的3.1章节。若无法达成令人满意的解决方案，则将采用数据插补法处理该问卷的数据质量问题，适用该方法的问卷需满足以下条件：所有调查条目至少完成60%、关键项至少完成80%、第16题与第22题至少完成60%。未达到插补标准的问卷将被视为无效问卷，并从本报告的分析样本中予以剔除。