( i ) Revenue Recognition The Companys revenue is generated from two revenue streams: contract revenue and assay revenue. The Company accounts for revenue in accordance with Accounting Standards Update (ASU) No. 2014-09, Revenue from Contracts with Customers (Topic 606) , as amended, and accounts for revenue in accordance with Accounting Standards Codification Topic 606 (ASC 606). The core principle of ASC 606 is that the Company recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the Company expects to be entitled in exchange for those goods or services. The ASC 606 revenue recognition model consists of the following five steps: (1) identify the contracts with a customer, (2) identify the performance obligations in the contract, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations in the contract and (5) recognize revenue when (or as) the entity satisfies a performance obligation. The Company recognizes revenue from its contract and assay goods and service in accordance with the core principles and key aspects considered by the Company. These considerations are described below, first for Contract Revenue and then for Assay Revenue. Contract Revenue Contract revenue is generated from the sale of laboratory services and adhesive sample collection kits to third party companies through contract research agreements. Revenues are generated from providing gene expression tests to facilitate the development of drugs designed to treat dermatologic conditions. The provision of gene expression services may include sample collection using the Companys patented adhesive patch biopsy devices, assay development for research partners, ribonucleic acid (RNA) isolation, expression, amplification and detection, including data analysis and reporting. Assay Revenue The Company generates revenues from its Pigmented Lesion Assay (PLA) and Nevome services it provides to healthcare physicians in various states throughout the United States to assist in a clinicians diagnosis of melanoma. The Company provides prescribing clinicians with its adhesive sample collection kits to perform non-invasive skin biopsies of clinically ambiguous pigmented skin lesions on patients. Once the sample is collected by the healthcare clinician, it is returned to the Companys CLIA laboratory for analysis. The patient RNA and deoxyribonucleic acid (DNA) is extracted from the adhesive patch collection kit and analyzed using gene expression technology to determine if the pigmented skin lesion contains certain genomic features indicative of melanoma. Upon completion of the gene expression analysis, a final report is drafted and provided to the dermatologists detailing the test results for the pigmented skin lesion indicating whether the sample collected is indicative of melanoma or not. (a) Disaggregation of Revenue The following table presents the Companys revenues disaggregated by revenue source during the three months ended March 31, 2020 and 2019, respectively, (in thousands): Three Months Ended March 31, 2020 2019 Assay Revenue PLA Test $ 796 $ 235 Contract Revenue Adhesive Patch kits 14 167 RNA Extractions 671 115 Project Management Fees 76 78 Other  1 Total Revenue $ 1,557 $ 596 (b) Contract Balances and Deferred Revenue The timing of revenue recognition, billings and cash collections results in billed accounts receivable and deferred revenue on the condensed consolidated balance sheets. Generally, contract revenue has a majority of agreements in which the Company receives a substantial up-front payment upon various milestones over the life of the agreement. This results in deferred revenue and is relieved upon delivery of the applicable adhesive patch kits or RNA extraction results. Changes in accounts receivable and deferred revenue were not materially impacted by any other factors. The Company records a deferred revenue liability if a customer pays consideration before the Company transfers a good or service to the customer. Deferred revenue primarily represents upfront milestone payments, for which consideration is received prior to when goods/services are completed or delivered. Deferred revenue at March 31, 2020 and December 31, 2019 was $1.1 million and $1.4 million, respectively.