SEER RRSS #2: Frequency and Predictors of Missing Data in Site-Specific Variable

SEER收集的特定地点变量的数量正在增加。 拟议研究的目的是评估SEER所需的特定地点变量的完整性，确定与缺失信息相关的因素，并量化收集这些信息所需的资源。 为了实现这些目标，将对2004年1月1日至2007年12月31日期间报告的关注癌症的数据进行检查，并计算2004年后添加到SEER中的变量的缺失数据病例比例。 将检查数据完整性与各种登记相关、患者相关、肿瘤相关和提供者相关特征之间的关联。 最后，将对六种特别感兴趣的癌症进行单独分析，以量化获得感兴趣变量信息所需的时间和精力。 SEER收集的特定地点变量的数量正在增加。 根据临床研究中报告的明显诊断、治疗和预后重要性，新的癌症特征不断被添加到SEER数据收集中。 阳性淋巴结的大小和囊外侵犯的存在已被证明是头颈部各种癌症部位的有价值的预后因素。 甲胎蛋白（AFP）和β-人绒毛膜促性腺激素（-HCG）水平有助于区分睾丸腺瘤和非睾丸腺瘤癌症，并用于监测疾病进展和对治疗的反应。 霍奇金淋巴瘤和非霍奇金淋巴瘤患者的治疗成功率和生存率与全身症状的存在相关，如盗汗，体重减轻和复发性皮肤瘙痒（瘙痒症）。 Gleason评分是影响前列腺癌患者治疗选择的关键因素之一。激素和单克隆抗体治疗的适应症分别基于雌激素/孕激素受体（ER/PR）和人表皮生长因子受体2（HER-2）的状态。 尽管这些变量的临床重要性已得到充分证明，但如果大部分病例的信息缺失，则这些变量在基于人群的数据中的效用可能有限。 还必须指出，这些新变量的数据收集可能需要大量时间和精力。 预计在某些情况下（但肯定不是所有情况下），编码特定于站点的变量所需的信息可能很容易获得。 例如，我们对格里森评分数据提取的经验表明，这种前列腺癌特异性变量几乎总是可以从病理报告中获得。相比之下，现在新诊断的前列腺癌也需要确定患者的诊断前PSA水平，这可能涉及更广泛的医疗记录检查，特别是如果PSA分析是在门诊基础上进行的。 由于上述所有原因，并且由于SEER对简化数据收集程序感兴趣，因此将确定报告特定地点变量的频率以及检查缺失数据的预测因素和来源。 其他分析将侧重于获取不同地点特定变量的数据所需的时间和精力。 我们的总体长期目标是根据数据可用性与收集这些数据所需的时间和精力的权衡，就是否需要纳入特定变量做出决定。

The number of site-specific variables collected by SEER is increasing. The objectives of the proposed study are to evaluate the completeness of the site-specific variables required by SEER, to identify factors associated with missing information, and to quantify the resources required to collect this information. To achieve these objectives, data will be examined for the cancers of interest reported between January 1 2004 and December 31, 2007 and calculate the proportions of cases with missing data for the variables added to SEER after 2004. The association between the completeness of data and various registry-related, patient-related, tumor-related and provider-related characteristics will be examined. Finally, separate analyses will be conducted on six cancers of particular interest to quantify the amount of time and effort required to obtain information on the variables of interest. The number of site-specific variables collected by SEER is increasing. The new cancer characteristics are continually being added to SEER data collection based on their apparent diagnostic, therapeutic and prognostic importance as reported in clinical studies. Size of positive lymph nodes and presence of extracapsular extension have been shown to serve as valuable prognostic factors for various cancer sites of the head and neck. Alpha fetoprotein (AFP) and beta human chorionic gonadotropin (β-HCG) levels assist in distinguishing testicular seminomas from non-seminoma cancers of the testes, and are used for monitoring disease progression and response to therapy. Treatment success and survival of both Hodgkin¿s and non-Hodgkin¿s lymphoma patients is associated with the presence of systemic symptoms such as night sweats, weight loss and recurrent skin itching (pruritus). Gleason score is one of the critical factors affecting treatment selection for prostate cancer patients. Indications for hormonal and monoclonal antibody therapy are based on the status of estrogen/progesterone receptors (ER/PR) and human epidermal growth factor receptor 2 (HER-2), respectively. Despite their well-documented clinical importance, the utility of those variables in population-based data may be limited if the information on a large proportion of cases is missing. It is also important to note that data collection for these new variables may require substantial time and effort. It is expected that the information required to code site-specific variables may be readily available in some, but certainly not all, instances. For example, our experience with Gleason score data abstraction indicates that this prostate cancer-specific variable is almost always available from pathology reports. By contrast, determination of the patient¿s pre-diagnosis PSA level, which is now also required for the newly diagnosed prostate cancers, may involve more extensive examination of medical records, particularly if the PSA analysis was performed on the outpatient basis. For all of the above reasons, and because SEER is interested in streamlining data collection procedures, the frequency with which the site-specific variables are reported and to examine the predictors and sources of the missing data will be determined. Additional analyses will focus on the amount of time and effort required to obtain data for different site-specific variables. Our overall long-term goal is to inform decisions on whether or not inclusion of specific variables is warranted based on the data availability weighed against the amount of time and effort required to collect those data.