Please assess the completion status of the following clinical trial:

Trial Title: The Mechanisms of Manual Therapy in the Treatment of Low Back Pain

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: SINGLE
- Phase: PHASE1/PHASE2
- Number of Arms: 4.0

Eligibility Criteria:
Inclusion Criteria:~* currently experiencing low back pain which does not extend below the knees~* rate the low back pain as a minimum of 4/10 at worst over the past 24 hours~* appropriate for conservative management of low back pain~* english speaking~Exclusion Criteria:~* surgery to the low back over the past 6 months~* systemic disease known to effect sensation~* other chronic pain condition unrelated to low back pain~* fracture as a cause of low back pain

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 60 Years
- Healthy Volunteers: f

Study Arms:
- spinal manipulation (Type: ACTIVE_COMPARATOR): a spinal manipulation known to be effective in the treatment of low back pain for some individuals
- sham spinal manipulation (Type: PLACEBO_COMPARATOR): a sham spinal manipulation intended to mimic the studied spinal manipulation
- natural history (Type: NO_INTERVENTION): No intervention is provided to participants in this arm of the study
- Enhanced sham spinal manipulation (Type: PLACEBO_COMPARATOR): a sham spinal manipulation intended to mimic the studied spinal manipulation and provided with the instructions, The manual therapy technique you will receive has been shown to significantly reduce low back pain in some people

Based on this trial design, predict the completion outcome and termination type (if applicable).