Discussion topic:
Choose an article from a literature search. Look at the abstract and identify the key components as mentioned in lectures. Paste the abstract here with a summary of what you noticed in its components underneath.
Discussion post:
Attached below are quoted portions of an abstract from the Stahl et al^1 study on fractionation methods of SBRT treatment in NSCLC patients. Below each quoted portion I will explain and identify the abstract’s key components. The below quoted abstract follows the informative approach typically used in research studies.^2 Information in this abstract is mapped out in the manner it is presented in the article and it provides details about each section in summary form.
Purpose: To determine the effect of biologically effective dose (BED10) and radiation treatment schedule on overall survival (OS) in patients with early-stage non-small cell lung cancer (NSCLC) undergoing stereotactic body radiation therapy (SBRT).^1
The preceding section of the abstract begins with a statement of purpose. It briefly summarizes the subject and context of the study. The research question is presented and the reader can determine the primary objective of the study. The “purpose” section of the abstract can also be used as an index when compiling several articles or as a means of review for management to assess the work of a staff researcher.^2
Methods and Materials: Using data from 65 treatment centers in the United States, we retrospectively reviewed the records of T1-2 N0 NSCLC patients undergoing SBRT alone from 2006 to 2014. Biologically relevant covariates, including dose per fraction, number of fractions, and time between fractions, were used to quantify BED10 and radiation treatment schedule. The linear-quadratic equation was used to calculate BED10 and to generate a dichotomous dose variable of <105 Gy versus ≥105 Gy BED10. The primary outcome was OS. We used the Kaplan-Meier method, the log-rank test, and Cox proportional hazards regression with propensity score matching to determine whether prescription BED10 was associated with OS.^1
The “methods and materials” section of an abstract expands on the design of a study and explains how information is gathered and categorized. Information on participants and the selection process is shared and briefly explained. Assessment methods of data and research are included in short form in the abstract. The “methods and materials” section of an abstract cites the process involved in gathering samples and the method behind analysis of gathered data.^2
Results: We identified 747 patients who met inclusion criteria. The median BED10 was 132 Gy, and 59 (7.7%) had consecutive-day fractions. Median follow-up was 41 months, and 452 patients (60.5%) had died by the conclusion of the study. The 581 patients receiving ≥105 Gy BED10 had a median survival of 28 months, whereas the 166 patients receiving <105 Gy BED10 had a median survival of 22 months (log-rank, P=.01). Radiation treatment schedule was not a significant predictor of OS on univariable analysis. After adjusting for T stage, sex, tumor histology, and Eastern Cooperative Oncology Group performance status, BED10 ≥105 Gy versus <105 Gy remained significantly associated with improved OS (hazard ratio 0.78, 95% confidence interval 0.62-0.98, P=.03). Propensity score matching on imbalanced variables within high- and low-dose cohorts confirmed a survival benefit with higher prescription dose.^1
The “results” section of an abstract is an opportunity for researchers to summarize findings of a study and provide the context for the information presented. Findings determined in the “methods and materials” section are summarized and presented as they relate to the larger breadth of the study. The end product of analyses are summarized and related to each group and any quantifiable values are presented in the “results” section of the abstract.^2
Conclusions: We found that dose escalation to 105 Gy BED10 and beyond may improve survival in NSCLC patients treated with SBRT.^1
The “conclusions” section of an abstract answers the research question presented in the “purpose” section. This is the opportunity for researchers to present their newly gathered data and relate their study to the currently available literature.^2
References
Choose an article from a literature search. Look at the abstract and identify the key components as mentioned in lectures. Paste the abstract here with a summary of what you noticed in its components underneath.
Discussion post:
Attached below are quoted portions of an abstract from the Stahl et al^1 study on fractionation methods of SBRT treatment in NSCLC patients. Below each quoted portion I will explain and identify the abstract’s key components. The below quoted abstract follows the informative approach typically used in research studies.^2 Information in this abstract is mapped out in the manner it is presented in the article and it provides details about each section in summary form.
Purpose: To determine the effect of biologically effective dose (BED10) and radiation treatment schedule on overall survival (OS) in patients with early-stage non-small cell lung cancer (NSCLC) undergoing stereotactic body radiation therapy (SBRT).^1
The preceding section of the abstract begins with a statement of purpose. It briefly summarizes the subject and context of the study. The research question is presented and the reader can determine the primary objective of the study. The “purpose” section of the abstract can also be used as an index when compiling several articles or as a means of review for management to assess the work of a staff researcher.^2
Methods and Materials: Using data from 65 treatment centers in the United States, we retrospectively reviewed the records of T1-2 N0 NSCLC patients undergoing SBRT alone from 2006 to 2014. Biologically relevant covariates, including dose per fraction, number of fractions, and time between fractions, were used to quantify BED10 and radiation treatment schedule. The linear-quadratic equation was used to calculate BED10 and to generate a dichotomous dose variable of <105 Gy versus ≥105 Gy BED10. The primary outcome was OS. We used the Kaplan-Meier method, the log-rank test, and Cox proportional hazards regression with propensity score matching to determine whether prescription BED10 was associated with OS.^1
The “methods and materials” section of an abstract expands on the design of a study and explains how information is gathered and categorized. Information on participants and the selection process is shared and briefly explained. Assessment methods of data and research are included in short form in the abstract. The “methods and materials” section of an abstract cites the process involved in gathering samples and the method behind analysis of gathered data.^2
Results: We identified 747 patients who met inclusion criteria. The median BED10 was 132 Gy, and 59 (7.7%) had consecutive-day fractions. Median follow-up was 41 months, and 452 patients (60.5%) had died by the conclusion of the study. The 581 patients receiving ≥105 Gy BED10 had a median survival of 28 months, whereas the 166 patients receiving <105 Gy BED10 had a median survival of 22 months (log-rank, P=.01). Radiation treatment schedule was not a significant predictor of OS on univariable analysis. After adjusting for T stage, sex, tumor histology, and Eastern Cooperative Oncology Group performance status, BED10 ≥105 Gy versus <105 Gy remained significantly associated with improved OS (hazard ratio 0.78, 95% confidence interval 0.62-0.98, P=.03). Propensity score matching on imbalanced variables within high- and low-dose cohorts confirmed a survival benefit with higher prescription dose.^1
The “results” section of an abstract is an opportunity for researchers to summarize findings of a study and provide the context for the information presented. Findings determined in the “methods and materials” section are summarized and presented as they relate to the larger breadth of the study. The end product of analyses are summarized and related to each group and any quantifiable values are presented in the “results” section of the abstract.^2
Conclusions: We found that dose escalation to 105 Gy BED10 and beyond may improve survival in NSCLC patients treated with SBRT.^1
The “conclusions” section of an abstract answers the research question presented in the “purpose” section. This is the opportunity for researchers to present their newly gathered data and relate their study to the currently available literature.^2
References
- Stahl JM, Ross R, Harder EM et al. The effect of biologically effective dose and radiation treatment schedule on overall survival in stage 1 NSCLC patients with SBRT. Int J Oncol Biol Phys. 2016:96(5):1011-1020. http://dx.doi.org/10.1016/j.ijrobp.2016.08.033
- Lenards N. Literature Review and Abstracts. [SoftChalk]. La Crosse, WI: UW-L Medical Dosimetry Program; 2017.