Dear Sanjeewa, maybe the following papers will help you on the subject:
Nyberg A, Hedlund M, Kolberg A, et al. The accuracy of using elastic resistance bands to evaluate muscular strength. European Journal of Physiotherapy 2014;16(2):104-112. https://www.researchgate.net/publication/262606664_The_accuracy_of_using_elastic_resistance_bands_to_evaluate_muscular_strength
Nyberg A, Lindström B, Aronsson N, Näslund M, Wadell K. Validity of using elastic bands to measure knee extension strength in older adults. Journal of Novel Physiotherapy and Physical Rehabilitation 2016, 3(1): 16-21. https://www.peertechz.com/Novel-Physiotherapy-Physical-Rehabilitation/download.php?file=pdf/JNPPR-3-130.pdf
Buskard AN, Oh J, Eltoukhy M, Brounstein S, Signorile JF. A Novel Method to Determine Optimal Load in Elastic-Based Power Training. J Strength Cond Res 2018;32(9):2401-2408. https://journals.lww.com/nsca-jscr/fulltext/2018/09000/A_Novel_Method_to_Determine_Optimal_Load_in.1.aspx#pdf-link
Kubo T, Hirayama K, Nakamura N, Higuchi M. Effect of Accommodating Elastic Bands on Mechanical Power Output during Back Squats. Sports (Basel) 2018;6(4):E151. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6316108/pdf/sports-06-00151.pdf
Lopes JSS, Machado AF, Micheletti JK, de Almeida AC, Cavina AP, Pastre CM. Effects of training with elastic resistance versus conventional resistance on muscular strength: A systematic review and meta-analysis. SAGE Open Med 2019;7:2050312119831116. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6383082/pdf/10.1177_2050312119831116.pdf
Batsis JA, Boateng GG, Seo LM, Petersen CL, Fortuna KL, Wechsler EV, Peterson RJ, Cook SB, Pidgeon D, Dokko RS, Halter RJ, Kotz DF. Development and Usability Assessment of a Connected Resistance Exercise Band Application for Strength-Monitoring. World Acad Sci Eng Technol 2019;13(5):340-348. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6570823/pdf/nihms-1028161.pdf
Jakobsen MD, Sundstrup E, Andersen CH, Aagaard P, Andersen LL. Muscle activity during leg strengthening exercise using free weights and elastic resistance: effects of ballistic vs controlled contractions. Hum Mov Sci 2013;32(1):65-78. https://www.sciencedirect.com/science/article/pii/S0167945712000917?via%3Dihub
Andersen L.L. et al. Validity and reliability of elastic resistance bands for measuring shoulder muscle strength Scand J Med Sci Sport 2016 provides an assessment for measuring shoulder strength utilizing elastic resistance bands. This article may help you.