retrospectively compared to each other？

The association between intervertebral disc pathology with low back pain and nerve compression pain syndromes (i.e., sciatica) has been long established [1, 2]. Studies have estimated that approximately 40% of lower back pain can be attributed to intervertebral disc pathology, from either acute herniation or degenerative disc disease [1, 3]. For clinicians, the decision to recommend surgical intervention versus nonsurgical conservative management has been challenging since both methods have been studied and demonstrated efficacy in treatment [2, 4–6]. When retrospectively compared to each other, surgical patients had improved pain and function [6]. However, the validity of these conclusions is restricted due to poor study design.

早已证实椎间盘病变性腰痛与神经卡压性疼痛综合征（如坐骨神经痛）存在关联[1-2]。研究估计，椎间盘病变（如急性突出症、退行性椎间盘疾病）导致了约40%的腰痛 [1，3]。对于临床医师来说，哪些该推荐手术干预或哪些该推荐非手术保守治疗具有挑战性，研究证实，这两种方法在治疗中都有效[2，4-6]。对这两种治疗的回顾性对比发现，虽然手术患者的疼痛和功能都有所改善[6]，但由于研究设计不佳，这些结论的有效性受限。

retrospectively compared to each other 对这两种治疗的回顾性对比？各位老师，是这个意思吗？谢谢