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act of agricultural outsourcing services on productivity and household welfare. 2) Also, we would have preferred more reliable pricing data for outsourcing services (e.g., task-specific prices). 3) In future research, we would also like to have more detailed data on migrations at the member level (vs. exclusively on heads of households). Future research on the effects of agricultural outsourcing on technical efficiencies would help guide the debate on agricultural outsourcing services on production and food security.Author ContributionsConceptualization: HG CJ SJ JY. Data curation: CJ JY. Formal analysis: JY CJ SJ HG. Funding acquisition: HG. Investigation: CJ HG SJ JY. Methodology: SJ JY CJ HG. Project administration: HG. Resources: HG. Software: JY CJ SJ HG. Supervision: SJ.PLOS ONE | DOI:10.1371/journal.pone.0170861 January 27,15 /Outsourcing Agricultural ProductionValidation: SJ JY CJ HG. Visualization: CJ SJ HG JY. Writing original draft: CJ. Writing review editing: CJ JY SJ HG. A 1.6.8-million-year-old hominin metatarsal from the South African Swartkrans paleoanthropological cave site makes osteosarcoma the earliest documented cancer of humankind1. Unfortunately, the only time period since then during which significant prognostic gains were achieved was from the late 1970s until the early 1980s, when combining multi-agent chemotherapy with surgery revolutionized treatment2. Unfortunately, the decades since have witnessed no further improvements of survival in North America3 or Europe4. Nevertheless, there have been numerous advances in the management of osteosarcoma which merit review and discussion. Osteosarcoma is a rare bone cancer which mainly affects adolescents and young adults. Though lower-grade variants exist, most are high-grade malignancies with a high propensity for lung metastases. Current standard treatment consisting of surgery plus chemotherapy leads to long-term, disease-free survival in approximately 60 of patients with localized extremity disease70 and 200 for patients with primary metastases or axial primaries7,11. Most patients are treated using a neoadjuvant approach, and histologic response to preoperative chemotherapy has emerged as an independent prognostic indicator7. While combined preoperative and postoperative chemotherapy has never been shown to provide survival benefits over adjuvant chemotherapy alone (as long as both contain the same cumulative doses)7,12, it offers time to prepare for surgery and allows an in vivo evaluation of the effects of systemic treatment. These may be estimated by a variety of imaging methods, but histologic assessment for the proportion of viable tumor remaining at surgery is the gold standard. Patients whose primaries respond well to chemotherapy, usually defined as